My dad's mk4 2.0 drank a ton of oil, my 1.8t was apart for a bit in 02ish so I was commuting 120 miles a day in his and I was topping off once a week, oil light would ususally come on Friday as I hit the NJTP exit 8a ramp... Nothing like warning lights once you've committed to a turn. He traded it in before there was a fix.
The other mk4 problem that most people don't actually know about is the soft rear pads on early cars. They put super soft rear pads on to keep the brake noise down. But in just normal Central Jersey stop and go traffic ( or similar places) people were going through pads in 20-30k. There's no pad sensor and the system was meant to use the brake fluid level as a low pad warning, but it only works if the fronts and rears are both worn. So people would come in with trashed metal in metal rotors and wheels that were destroyed from all the burning metal flakes hitting them. We had an asst service manager who insisted all these people must be riding with the parking brake on and refused to warranty them until VW finally did a bulletin.