Welcome!
I had a mk6 GTI back in 2009 with one of the very first REVO maps for that engine. Money very well spent!
I had another a couple years later and put a Bluefin map on it just to see how different it was.
Rtech are good I’d think, they’ve been doing their thing for a while now.
Stage 1 is as much as you’d need for road use but if things are wearing out then replacing with uprated and going stage 2 will give you that little bit more.
Personally I’d stick with stage 1.