OTS is fine and most are on 93 tunes. Stock DP is limiting, but you can run it without issueGoing IS38+ on my GTI, as I interpret the "plus" details to imply a higher limitation as opposed to the OEM IS38. I'm planning on running the factory downpipe from my IS20 for the time being, should I simply get an OTS IS38 tune for the time being? Is it dumb to stay on stock fueling (93 is the plan this time around)? I'm not looking for massive numbers, I just know that I'd like some more top end out of the car -- the lower area of the rev range is delightful, and I'm just looking for a bit better top end to match. In the future I may consider HPFP and E30, but I looked into the Vortex standard and don't think it's for me, at least not with a FWD GTI.