I like the Armattan Badger 5" frame so far. This is quite a heavy build, with the GoPro it comes in at 790g, and you can feel it. In some ways its awesome, it builds and carries momentum very well, but also is not quite as responsive to very quick changes in direction. Still working on the PID tune, maybe it will get even better.

Update, April 2021: At first I was not thriled with the preformance of this quad, it flew well but diddnt rip as hard as I wanted. After testing many different prop combos, I have finally found the key is rather high pitched props. This thing is heavy, 680g with no GoPro, and 800g+ with a fullsize GoPro. I have recently ben flying Gemfan 5152S V2 props, the extra .1 of an inch diameter and 5"+ pitch make this quad scream (in a good way) with no GoPro, and flies exceptionally well with the GoPro the props aren't light at about 5g and I was concerned about battery length/life with the high pitch and weight, but this is where these motors shine. The T-Motor Velox 2306.5 is marketed as "a perfect choice for those larger prop 6S builds" and they are not lying. Im still tweaking the pids but, all things considdered, running a 1300mah 6S battery and the 5152S props I get about 3.5-4 min with the GoPro and 5+ minutes with no GoPro doing my "freestyle" type flying. Click to watch, https://www.youtube.com/channel/UCR6B8ZOM6alO15ev8JVbbpQ.