It is my favorite car ever! so awesome and a pleasure to drive every minute!
stalling failure has been pretty much addressed by a TSB that will automatically be scanned and applied if it hasn't, on any purchased vehicle. ....and if it doesn't happen to work on your particular GTI, it just adds to the charm!
Rev Hang is indeed pretty shitty, but can be addressed by removing the diverter valve thingy, clutch spring, and bonus: adding a stop to the floor to reduce the clutch travel.
Italian tuneup every month or so fixes your potential carbon problems for the most part....it's not as bad as it has been in the past, supposedly, and it really isn't anything you should worry about under 70k miles anyway, I think.
The back sucks for tall people, though. It does suck that they stopped making 2 doors a few years ago, especially considering that the rear legroom isn't amazing anyway. I think there is plenty of space up front, however, at least up to 6'3" or so (assuming no one wants to sit behind you).
Standard clutch is kinda weak, though. If you have thoughts of tuning up to stage 2 (maybe even 1, in some cases), you might have to replace the clutch because it can't handle much more than 280 torques, or so. ...supposedly. ...and then there is a problem, because the thrust bearings are garbage and when people replace to aftermarket clutch, crank walk becomes a real problem. VW seems adamant not to address the fact that they installed a garbage clutch assembly/crank/whatever to begin with, that is causing the bearings to blast through your engine casing if you install something heavier that can you know, handle Golf R level torque
VW is kinda nonsense, because the Mk8 GTI is kinda wack. ...maybe it will grow on people, but I don't like the all-digital cockpit and all capacitive buttons on infotainment. The front looks broke, too. That will be out for the 2022 US model year, I think? Unless we are still on 2020 Mk7.5? not sure if Mk8 comes here with 2021, as originally scheduled, but it might have been delayed--there was a serious issue with the Mk8 released in Europe market for 2020. Go figure. I forget what it was, though.
....You will still want to try and find a 2019 or 2018, though, to get the last year of People's Warranty (7 years/60k miles). back to 3 years on 2020.
....Only real issue with mine is that some freak ants have decided to turn the filler chamber and rear/front passenger doorjambs into their nest. I eat no food inside, keep that mother clean as all hell....and yet these assholes have turned it into their lair (not really the cabin, though you will see the occasional one). I noticed a group of them standing sentinel last year, outside the gas cap, when I went around to fill it...weird motherfuckers, too. locked together in a phalanx with the business end pointing up for attack. I swiped them away then forgot about them, until about 3 weeks ago when opening that rear door, which is never used, during a rain storm to load in some drywall, and noticed that the entire doorjam was swarming with terrified little bastards shuffling their larvae around.....and I don't think these are neighborhood ants. It doesn't make sense. I strongly suspect they shipped with the car from the plant in Mexico, which I know is a thing that happens (there was some TSB years ago about neon yellow spiders and Mazda cars built in Mexico--Mazda actually owned up to it).
I'm thinking of collecting them when I can (I tried to vacuum up most of the colony, but I know that isn't a real solution), smash those fuckers, extract their DNA in lab, and send them off to add to a friend's next-gen seq queue. I'm going to locate those fuckers in Mexico, very close to that plant based on their haplotype, and send that data to VW if they give me any static, lol.
Anyway, go for it! But if you do have plans to tune it for sure (I don't), then I would consider looking at a deal on a Golf R if you can find one, because you're already investing in that performance from the start, no anxiety about blasting through your engine, or stalling and all that stuff. (or illegal ants immigrating from Mexico with your car--all Golf R's are still made in Wolfsburg)