Spend the money and buy new. You'll be much happier.
Buying a used GTI/R (or WRX, or Civic Si, or...) is like marrying a cheap hooker ten minutes after you meet her. Roll those dice.
Disagree. I've owned a few used cars that fell into that general category (Civic Si, RSX-S), and while most people don't buy the performance trim to drive slowly, it doesn't mean the cars weren't treated well. The number of threads on this forum posted by people who obsess and agonize over which oil/tires/interior cleaner/washer fluid/etc is best for their GTI illustrates my point. If anything, you're better off buying a used enthusiast car than a used family sedan, which was almost certainly treated indifferently, as one would treat any other appliance.
That said, not every used performance car is going to be a burnished specimen of perfection. Lower miles are obviously better, and it's worth it go out of the way to find a one-owner vehicle. The older that one owner is, the better, and never buy any vehicle that's been in a collision, regardless of how minor they say it was.
If you were to sell your own car, would you describe it like it was a horse on its way to the glue factory? No, I'll bet you could write a book on how much time you've lavished on your car, and most everyone here could do the same. When the time comes to replace my GTI, someone's going to get a 2017 Sport with low miles (roughly 840/mo) that's been lovingly maintained, but driven in a spirited fashion, as it was designed to be.
It's the cars that are on their 3rd-4th driver that are more like your hooker example, because those owners didn't spend nearly as much money on them.