Definetly go 4 Guage. I started with a 10" and a 180W amp. When I got my new Amps and told the guy I was running 8G wire he started laughing at me. Then I showed him my 30A fuse and he laughed again. 4G will be a bit more but will be worth it in the future.

The Honkeytonk Monkey - Jewel Green 96se MTX