I've read here about guys upgrading their 3.5G tanks to 5G's because they are tired of stopping to fill up every 120 miles or so. My 08 DX is a 5G and 120 miles is all I have ever been able to get out of a tank. It is the 1250cc, all stock and it doesn't seem to matter much if the miles are all city or all hwy. Plus it's a California bike which is mapped leaner than it should be for our special little EPA regs. I'm concerned my MPG's will get even worse after I do the pipes, fuel manager and K&N topless. Stopping every 100 miles or less is going to get real old real quick.