Roller coaster with lap band?

Hi, I had my lap band surgery Febuary 4th 2011, Im going to carowins july 4th 2011. Is it safe for me to ride the roller coasters? It has been 20 weeks, so im guessing is okay, but does it feel any different with the lap band? Does it hurt? Will the rough ones that sling you around and jult you a lot be dangerous? My doctor said after 6-8 weeks I could do anything, he said I could even go sky diving. I was just wanting some personal experiences.. Thanks.