2008 GLI, 160k miles
Had car since new and still on original clutch. Done oil changes every 5k, air and cabin filters every 20k, fuel filters every 40k, coil packs and spark plugs twice, and one battery change. I'm still getting 29mpg combined on premium 91 gas.
Had a PCV failure and a fuel pressure sensor malfunction early on, but all replaced under warranty.
Had some boost hose leaks, but replaced them with Forge Silicone ones that have been leak-free for over 7 years.
Thermostat failed around 100k, but ended up having the timing chain and water pump done also.
AC went out shorter after and I've since disconnected it by using a shorter belt.
I've developed a very slow oil leak but i think it's a damaged oil filter housing as it has been soiled the last few oil changes.
I have yet to clean the intake valves and the car still gets the same mileage and power as new. I still get false, rear tail-light burnt out warnings periodically though. This drives you mad and I have tried everything and found that bending the contact clip for a tauter fit helps the bulbs stay lit.
I highly recommend deleting the noise pipe system that re-routes compressed intake air to a small "speaker" horn in the passenger-side firewall. Since removing all of the plumbing and parts with the Audi A3 throttle pipe, it sounds more natural and spools noticeably faster. I've also replaced the diverter valve to the upgraded, piston-type one found on newer MK5s.
Make sure to check that cam follower in the HPFP periodically, my car isn't chipped, over boosted, nor do I drive it hard daily but I did check it once before 100k and it was still great with no wear nor discoloration but I replaced it anyways.
Overall, the car still pulls hard, fun to drive, good on gas and insurance. I do regret not getting the 4-door GTI as the hatch offers more practical usage.
I have done an array of other mods that I could've done without and have since returned the car back to stock, stock is always the best in the end I hate to say. Drivers Wanted.