I had my previous Merc ML Diesel stolen twice from my house, both times keys were taken. On each occasion the car was driven about 20 miles away and parked in a residential street. Both times it was left parked perfectly and locked up. It had a tracker and was recovered by the Police on both occasions. First time took 5 days, second time took 2 hours.
Thats when the fun starts as the car is then taken to secure lock up for finger printing and then on to a Merc dealer to have new locks fitted. ( need passport for that ). That takes about 10 days while you have to drive around in a courtesy car. At this point you find out how good / bad your insurance company is.
Each time it came back after having a full diagnostic check, full valet and wheel alignment which I insisted on, so I was quite happy to take it back. It was also not registered as stolen / recovered which is important.
I was lucky it was in perfect nick both times having been apparently 'stolen to order'.
Nobody was ever caught and Police never came back to me after that.
I now have CCTV, dog and house alarm. Front and rear doors are all deadlocked now as well.
If the GTi was stolen that would be different I think. Maybe it would be used in a getaway and be thrashed as it is a different type of car.