I had to assume that you are going to frame mount this winch so I voted for the 2.5. If this is indeed the case, I fear you will not be able to fit the 3.0. Now if you go with the hitch mount method, like grizzlywizard, I say go with the 3.0.
Why would I go bigger if I could? Winches are used to get unstuck or perform other heavy duty jobs. Lets face it, if we're stuck, we want the max available power to get us out easily in the worst of conditions ESPECIALLY if you're riding solo. I have the 2.5 but it was free with the quad. JMHO.
Let us know what you get. I love new stuff even if it isn't on my quad! :headbang: