This is a review for the BenQ HT2150ST. Seeing as Amazon combines numerous models into the same review pool, I felt the need to specify. I have only had the projector for a couple days so this is a honeymoon-phase review and I will try to remember to update this review later on after I have had a while to put it through the ringer. I will compare the 2150ST to the Optoma GT1080 in this review as well. Having said all of this, let's get to the review.**Picture Quality**This projector's picture quality is simply remarkable. I am highly critical of anything I purchase with my evaluation of electronics being especially stringent. Compared to the Optoma GT1080, the BenQ has better colors; equal or better black levels; less rainbow effect (abbreviated RBE); and better focus uniformity (perfect). Many people are concerned about the rainbow effect, so I am here to say that it is all but non-existent on the BenQ. The Optoma had some rainbowing that wasn't bad by any means, but it did show up without even purposefully looking for it. It didn't bother me much, but having now used the BenQ I feel spoiled. Quite literally the only way I can even observe the RBE is by putting up a high contrast scene like the grid test pattern and darting my eyes across the image. Even then it takes a few passes with my eyes to find it. The black levels are as dark as or darker than my TV (Sony KDL W700B). For empirical comparison the Sony TV has a Black level of about 0.020 cd/m2 (taken from the W800B review on Rtings.com. The W800B is the W700B, just with 3D). This is with my projector being used on a light-green wall. Theoretically a darker wall would improve the black levels and contrast overall. The colors are even better than the Sony TV and much better and more natural than the Optoma (This and the lack of RBE are thanks to the 4X/6X speed, RGBRGB color wheel compared to the Optoma's 2X speed, non-RGBRGB color wheel). The final point of comparison in this category would be focus uniformity. Here the BenQ takes the win with no question. The Optoma had fairly blurry corners as well as chromatic aberration (especially the top right corner) when the middle of the screen was used to adjust focus. This resulted in me having to find a happy middle-ground between top-right corner focus and center picture focus. The Ben Q immediately provided perfect focus without any chromatic aberration across the entire ~135" image. In short, the picture quality on this projector is remarkable.**Operating Experience**This section is meant to address the ease of operation, the operational capabilities, and the things that may be easily overlooked by potential projector purchasers. First of all, the BenQ has MANY more options provided in the menus than the Optoma. They both have digital, vertical keystone and the usual gamut of gamma, color, contrast, etc. settings. The Ben Q, however, has many other settings on offer for the person who really wants to tinker with the projector. My personal favorite is the color correction option that adjusts the image based on the color of the surface you are projecting upon. The remote has all of the things that you use frequently/somewhat frequently on it (I will post a picture). Please note that at least one of the buttons (PiP) is a dummy for this model, at least as far as I can tell. The remote also has a red backlight (Woohoo! Backlit remotes just like the old days!). The brightness of this remote is much more usable than the blue backlight on the Optoma's remote (the Optoma's was positively blinding).The BenQ has a slightly longer requirement for projection distance than the GT1080, but both being short throw in nature, this isn't a huge problem. You can look up the specific values for yourself if you want more detail. The BenQ is also slightly more forgiving than the Optoma when it comes to placement due to its 1.2X zoom capability. This also has a VGA port and a Serial port which the GT1080 does not.**Value**Seeing as this projector just released a few months ago (August 2016) it is at full price, $1000 (~$1060 after Michigan taxes). I am not at all upset with the price I paid considering the quality I received. The Optoma left me a little underwhelmed, it lacked a bit of color and the issues I mentioned earlier bothered me enough to return it after about a week, at which time I decided to purchase the BenQ instead. Now, the Optoma is around $400 cheaper than the BenQ, so yes the BenQ should provide better overall quality. The GT1080 is not a bad projector, I know my words may make it seem like it is, but this is an objective, critical review, there are no participation ribbons being given. For me, even though the Optoma is much cheaper, I think the BenQ has a better value, the higher price point is more than made up for.**Gaming**I'll keep this short and sweet. There is no perceivable input lag. I would say it is equal to or faster than my Sony TV (24.3ms via Rtings W800B review). Remember, INPUT LAG AND RESPONSE TIME ARE NOT THE SAME THING. atleast 70% of the time when I see someone say "response time" they actually mean input lag. Input lag is what makes your controller seem out of sync with your TV, like when you hit a button on the controller to make your character do something and there is a delay before your character on screen actually executes that command. Most people can't notice anything less than 30-35ms, while some people can notice anything above 10 or 20ms using a controller, although at that point it isn't really a problem even though it can be noticed.. Response time on the other hand has to do with how quickly the pixels on your screen can change color (usually gray to gray or black to white). Response time on any respectable display will be 5ms or less. A slower response time will lead to "smearing" or "blurring" on your display. Think of it like in a movie or show where the character takes drugs and everything seems to look really flowy when they move or like they have a trail following them. That is an extreme example, but it gets the point across. This projector uses Digital Light Processing (DLP) to create its image, with DLP any ghosting/blurring is actually impossible from what I have learned through numerous articles. I never see any response time symptoms as I shouldn't. Think of it as posessing a response time of 0ms.**The Little Things**Both the Optoma and BenQ came INCREDIBLY well packaged. The BenQ even more-so. The remote for the BenQ has a satisfying tactile feedback/click to it. Both projectors have built-in speakers should you need them. I haven't used them on either one so I can't comment on their abilities, but they are there. If you are buying a decent projector, you should have something better than the built-in speakers to use, hence my avoidance of using them. However, they do have their place. It's really comforting to know that I can bring the projector over to a friend's house or outside and, with no further equipment besides a Blu-ray/DVD player, have a movie theater-like experience, especially with the short-throw nature that makes it easier to find a spot to project.**Negatives**If I had to pick out some negatives, it would be that the black level could be better and it could run a bit cooler. It is not plasma level or OLED level blacks, but it is most certainly as good as the high-end LED TVs. The temperature level isn't something that affects my viewing environment in any substantial way, however, being a techie, it bothers me when any piece of technology runs hot. Perhaps this high heat is just inherent of traditional projector lamp technology, but it still bothers me. In all honesty, these are the only things I think could be improved on this projector. Also, at this price point, I don't think you will find anything better. When I update this review later on, I will be sure to include any new or exacerbated issues that I encounter.**Conclusion**If you are deciding between the Optoma GT1080 and the BenQ HT2150ST, get the BenQ. They both are good projectors, but the BenQ is a tier or two above the GT1080 in quality and experience while coming in at a price that is only 1 - 1.5 tiers higher.**Full Disclosure**I purchased both the Optoma GT1080 and the BenQ HT2150ST with my own money. I was not in any way, shape, or form compensated for the review of these projectors. I am just a 22 year old college student with high standards and the desire to give credit where credit is due and call out any downfalls so that they can hopefully be improved upon in the future.Being one of the first reviews for this product, I really hope this is comprehensive enough for anyone looking to purchase this projector. Thanks for reading!