I came to Amazon to buy a JBL Flip 3 based a widely positive reviews and a desire to have a speaker that I could use outdoors without worrying too much about sudden showers, dust and other hazards of the elements. While searching for it, however, I came across Anker's newest entry, the SoundCore Sport XL. Given the price, my general satisfaction with Anker, and Amazon's solid return policy, I decided to give both speakers a try. I'll note that the SoundCore Sport XL is probably more comparable to the JBL Charge 2 given that both units have a USB port to let you charge your phone or other device. The Flip 3 doesn't have charging output port.If you want the shortest possible answer: We're keeping the Flip 3 and giving the SoundCore XL as a gift. But it was almost a coin toss about which was going to stay.Sound:I wanted this speaker to have enough volume for modest outdoor gatherings (both meet that criteria, though the Flip 3 is probably a touch louder) and sound good enough that I wouldn't mind having it playing in the house. I'm also biased against today's tendency for consumer speakers to emphasize bass response over every other frequency range. If you like your music boom-y, I'm not going to like the same speakers that you will.My wife and I listened to each of them across a wide range of music from classical to folk to hip-hop to pop to hard rock, trying to get a sense of which we liked better. The answer, as it turned out, was "it depends." The Flip 3 is definitely not as "flat" audibly as the SoundCore. Within the limits of what you can do with a small speaker, the Flip seems to emphasize the bass and treble ends of the spectrum more. High treble even sounded unnaturally "sizzly" for a couple songs. In others, the vocalist almost seemed a bit buried under the rest of the mix--though never disturbingly so. (We're talking nuance here, and your ears may have a different experience.)The SoundCore is definitely more flat sounding. It doesn't produce as much bass as the Flip, but that's not necessarily a bad thing, and it never had the sizzling issue in the treble. It just sounds...even. People used to the punchy sound emphasized by consumer speaker and headphone manufacturers, however, may find that the music lacks a bit of life.Which did we prefer? Ultimately it depended on what we were playing. Folk, country and music from the 70s and 80s that clearly was mixed with the intent of playing over the radio we often preferred on the SoundCore. More current pop, rock, and hip-hop sounded better to us on the JBL. In the final count, the JBL came out on top, but not by much. I've been listening to both for a few days now, switching back and forth every so often, and I find that I'm inclined toward the JBL, but I certainly don't mind the SoundCore.Size and Build:The SoundCore Sport XL is about 7 x 3 x 1.75 inches and wrapped in what feels like very sturdy, slightly rubbery plastic. It's definitely heavy in your hand and makes you feel confident that it can hold up to some rigorous outdoor use. The biggest issue with the design is that I found myself constantly grabbing into the bass port on the back, which includes a metal cover over a stretchy membrane for a passive woofer. I have no idea if pushing on the cover would damage the passive woofer, but it was disconcerting.The Flip 3 is 6.5 x 2.5 inches and covered in a dense fabric with hard plastic ends. It's slightly lighter in the hand, and the cylindrical shape makes it more comfortable to pick up and carry around. It feels solidly built if not quite as tank-like as the SoundCore. The Flip3's dual bass ports are on the ends, out of the way unless you have a very odd approach to picking up cylinders.