I always had a tough time on Sullest until I learned about how the missle silos ignore you at top-end. In the Naboo, make one pass around the place at top speed, taking out the missle silos and any guns you can squeeze in during that pass. Then, then next pass around go after the shield generators and any other guns. Also, the thing in the middle doesn't seem to get affected as much if you're close in, so back out and come back in occasionally. Ignore the fighters, but when you're shooting at the lighted things you can aim up or down a bit, and a few will fly right into your fire!