OK, Recenlty got around to putting on 225s, I took the plunge for the Goodyear Eagle F1 assymetric. First I replaced upper and lower wishbones on the front, uppers were shot (again) and lowers had a little slack in the big bushing. The set of four was nearly as cheap as the uppers alone on fleabay. Anyway, banged on the new tyres, my fiitter was full of praise for the F1, said they rarely require balancing as they are so well made, (three of them didn't) so that was a good start. I was a bit anxious, as the F1 225s were more than 10mm wider than the incumbent Falcon 215s, more like 22mm wider, so the clearance on the inside reduced by 11mmm, leaving just 5mm. Phew. A couple of weeks on the road now and the results are astounding. The extra width, depth and the F1 tyre itself all combine to transform the ride. Bad roads produce only half the clunk and rattle previously experienced, grip and cornering is amazing, especially in the wet, and road noise is drastically reduced. I literally couldn't believe the difference on the motorway at 120km (75 mph). A guy in a Tiida drew alongside, and the noise of his chariot was deafening through my windows, so quiet was it inside (no Tiida jokes please). I wouldn't have noticed this before, so I'm assuming both tyre brand and the up in size have caused this. Due to suspension renewal I have to get the tracking done so I'm limiting driving till then, though it seems straight as an arrow. Probably the best upgrade you can do to a GT, at least with these tyres. Oh yea, fuel economy is better, even allowing for the fact that the MPG meter reads 5% lower due to the diameter increase.