Honestly, you need to ask, and be honest with yourself about what you want out of whatever you buy. You can "get anywhere" in a lot of things. How fast do you want to get there, how comfy do you want the ride to be.. (suspension, travel) I drive a 15' xp1000 4 seater with a few things done to it. I am very happy with it, but I have to have the peddle on the floor all the time to dune the way I like to dune. I know myself and I wouldn't be happy with a 900. Would I enjoy a turbo more? Probably..I like to go fast.
Know what you want out of your new toy, and buy the most you can afford. But no, you don't NEED a turbo at all.