Hi,
1) So do you have estimate price range for the 15" rota slipstream or boost ? And which shop do you recommend ?
2) Wow, thought the lesser the spoke should be lighter.
New lesson gained.
3) O.K, then I stick to Bridgestone GR-80 tire then.
Once again, Thanks for the trouble to answering my silly queries. Have a nice 2008 ahead. 
estimated @ $120 per rims or so.
i strongly advise you to try V2. it isn't inferior to V8. just another name.
once you've tried it, you will never want to use GR80.
got a friend who tried V2 on my recommendation, a 53year old uncle.. driving a old honda civic. his car has gone 50k (constant malaysia goer) and his tyres still look fat and ready for another 10- 20k. dont get me wrong here. he's pretty agressive in driving and he likes the grip and noise level.
cheers. hope i've answered your questions and cleared your doubts. =]
btw, if you wanna do up your audio, do look for me.