Time for Head Work Yet? Or...?

I mainly ride on trails, and occassionally on sand dunes. Basically I want a little more power. My wallet isn't empty, but its not bottomless. Keeping under $500 or so would be nice. But then again so would a 400ex....in due time. So, should I port/polish, deck, and get a cam. Or...?
thanks

from what ive seen the 330 kit will make the 300 haul the mail!
maybe im slowin down in my old age..but i got smoked by a 330ex
and when i took it for a ride i was very impressed.