Having owned a couple of V8's, an XU1, and now the GTSt, I have tried a shitload of different tyres. Including, Yokahamas (352 I think), Bridgestone eagers, blah blah blah blah. They were all great tyres for grip, but because of the softer compound, they didn't last for any more than a year.
On the Skyline I went through all this question/answer/pricing crap in January this year, and arrived at the conclusion that I would try a middle of the road brand. I think it was in MOTOR magazine they did a run down on a heap of performance tyres and rated them albeit the opinion of the drivers they used.
You may want to take a look at Federal SS595's. I.ve had them since Jan and they look brand new still. For those who like a nice looking tyre, they fit the bill, and they come in a wide variety of sizes i.e. 16, 17, 18 and they're working on 19 and 20's. As for aspect and width, you should be able to get almost any size you need.
I have them front and back and am quite happy. To be quite honest, I don't think any but the softest compound tyres would be any good in the wet on a powered up GTSt. So you may as well not rip yourself off, and just take it easy in the wet.
Cheers Ozzy
http://www.federaltyres.com.au/news/release_ss.htm