The three of them are almost 100% identical for performance. The 3000 feels a little slower at times due to the microdrive. (Takes about 10sec longer to boot, programs load slower the first time, etc. 6sec to load opera on the 860, 12 on the 3000. If you cancel and reload the program it is exactly the same on both...)
Battery performance feels about the same - I'm not too worried about total run time other than "Long enough to get through my day" so I haven't run extensive tests.
If you don't find the extra features compelling - better keyboard, 4gb HD, USB host, then there's no point to upgrade. Personally, after using the 860 for a few months I found lots of situations where having the internal storage and USB host would save me lots of trouble and/or enable something I couldn't do before. Getting a 3000 was an absolute need for me.
For someone who's just looking for better battery life or faster performance - look elsewhere. You won't find it in these models.
