I'm a jazz improviser, and I'm using this looper along with an EHX Bass9 to perform solo. It is exactly what I expected after reading its description. Overall the functionality and experience is similar to what I get from my Spark2 looper but in a pedal format.
I previously had a Boomerang which was awesome but also was large and frankly required me to remember too many details to perform live flawlessly. Though the manual for the GL100 is 35 pages long, I find it intuitive after just a little practice. The touchscreen + rotary dial are easy to use.
The auto-record and drum machine (or flashing LED if you prefer) do indeed guarantee a perfect start and stop every time. The two footswitches make it very easy to reliably dub, undo/redo, and stop. The auto fade out (2 speeds) is useful, as is the wide range of tempo values. Overall it's a big improvement over the 1-button loopers I've used.
The built in drum sounds are good but for the most part are loud and are not at all subtle, more suited to rock than the music I play. But I can make my own drum loops on my Mac and load them.
Minus one star for quality since it played random stuff until I updated the firmware. Minus another star since the Mooer Studio software is not signed correctly and was (rightly) a pain to install on Mac; Mooer Studio works but is very slow.
Other improvements I'd like to see and would pay for: Ability to name the loops in Mooer Studio so I don't have to remember numbers. Support for 2 (or, better, 3!) simultaneous loops. Stereo 1/4" inputs & outputs (as opposed to 2 mono inputs/outputs). MIDI clock input.