Sounds good. I put some 285's on the other day. There isnt much space between the tyre and inner guard though. So I doubt much larger will fit, though Mysty has 295's on his.
I looked at proxies but decided to go with 4 Vredestein Ultrac Sessanta yesterday. I know they are still new, but the grip in the wet over the previous Pirellis on the front and Dunlops on the back is amazing. Hopefully it will stop raining soon so I can try them in the dry.