Which one did you get in the end?, I'm guessing your just using it for IEM's?
I have experience with both of these and much prefer the Khadas Tea for SQ, sounds more natural, also I like that it's single ended only so all the power of the amp is directed to that jack, where as on the BTR5 it has a 2.5mm and 3.5 mm jack, the 2.5mm higher power output than the 3.5mm, thus requiring you to purchase extra cables if you want to take advantage of the extra power, that being the output from the 3.5 jack should be more than enough for most IEM's.
I also wasn't that impressed by the Bluetooth performance of the BTR5, sometimes it even cut out with my phone on one side and the device on the other, Khadas Tea was much better in this respect, no cut out all.
Currently I'm using the Qudelix 5K, probably one of my fav portable bluetooth dac/amps, not quite as good sounding as the Khadas tea, but it makes up for with the wealth of options and settings it has in the companion app, and most impressive is the parametric equalizer, it even has pre-sets for hundreds of headphones and IEM's.