Yes. I've made scan codes fully compatible with Keyrah (main map). So i can use all tweaks i've made for Keyrah.
A500 controller on eBay ~6EUR. Chinese clone
of Sparkfun Pro Micro ~5EUR.
So, basically it's cheaper than Keyrah if you don't afraid soldering
But my main intention wasn't price (Keyrah isn't expensive actually) but bugs in Keyrah firmware. I've mentioned above it doesn't allow to press some keys together. And it includes often used combos like cursor UP+LEFT+LSHIFT(or LALT - need to check again). Or similar combos. So, this bug annoyed me a lot.
With A500 controller i have no such problems.