....Bridgestone Potenza = leave it in the garage when it rains!....
I've read some reviews and they do not seem to indicate very bad performance in wet.
Have you tried them yourself, TT? On what car? 
I think mine will come with Potenzas.
Trust me, they are shocking.
I've used S-03 PolePosition on a Vectra-B GSI - not as good as either Yoko AVS Sport nor Mich Pilot Sport (original directional tread), loads of wheelspin in the wet.
I've also used the RE040 and RE050 on a variety of other cars, including VX220, Vectra-C GSI 3.2, Vectra-C 2.0 TDI, Vectra-C 2.2 petrol, Peugeot 407, Mazda 6 - and probably some others too. The biggest problem with these, irrespective of the type of car, the engine, the driving style - was just a horrendous lack of cornering grip in the wet. No amount of experimenting with tyre pressures would lead to any kind of improvement.
I personally haven't used them on the GTI, but another poster here, Schrodingers Cat <sp?> also complained of utter shytness from his Bridgestones.
Oh, another snippet of info - don't believe any of Bridgestones advertising drivel, regarding F1 technology! An F1 tyre is a quantum leap away from high performance road tyres. How many high performance 13" road tyres, with side walls as tall as a small volcano, have you seen?
