R5gtt. Just a bit of advice. You can take it or ignore it.
I might not have posted this had I not seen your other thread, of a similar theme.
Doing 120 on a motorway is silly. You might be a great driver, I don't know that. But even if you were, there are too many other factors out of your control:
Other drivers in front sharing the same road. Who might not be the best drivers themselves. You're gambling on them not only seeing you in their mirror, but making an accurate judgement on your speed. A casual driver might not be able to discern the difference between a car doing 80 and a car doing 120 from a cursory glance in their rear view mirror, if they even use their mirrors at all. So then they move out to lane 2/3 to overtake a slower vehicle, into your path, leaving you on the brakes. At 120.
Rubber. Are you running the correct speed rating and load rating for a mk5 GTI? Could you state those specs without resorting to Google? Not many could, admittedly, but not many push that envelope so that it quickly becomes relevant. Tyre failure at 120 will be loads of fun all round.
Mechanical failure.
Unexpected tailback.
Obscure hazard.
Another crash, in your path.
The bizzies.
Seriously mate, turn it down a few notches. Yes, these cars are quite quick. But it's just asking for trouble doing that. I know you'll read this and think I'm being a killjoy, I'm having a go, whatever. But if a tiny bit of it sinks home I don't really mind what you think. Nobody wants to see "RIP R5gtt" on the forum do they? I don't.
Plus, and this is by far the biggest criticism I can throw at you...
How the hell can you enjoy the balance and response of a mk5 GTI, the best thing about the car, on the bloody motorway?!