Theres a crucial factor here...All wheel drive or a fandago diff.
Trying to put more than 200bhp through the front wheels is always tricky to pull off without some sort of major traction control system(GTI,Cupra..in fact,all hot hatches!),all wheel drive(S3,Type R?) or a fancy e-diff(Focus,Megane)
If VW are going to put a car into production with 300bhp,then it's going to be the range topper that has it...the R.
The GTI is the gentleman racer of the bunch and it's pretty much the essential all rounder.