yes. The 3100 is leaps and bounds better than the 5500. Battery life is average for the high end PDAs these days. The VGA on the 6000 is the best, but the 3100 is still impressive.
The pros of the 3100 over your experiences with the 5500
- battery life is better
- if battery dies, you don't lose all your info and settings
- 4GB of storage
- USB host
- VGA
- better quality build
- more ROMs to choose from
- better keyboard with dedicate number keys
- 64MB RAM
- landscape mode (also rotation on the fly)
- much more software available since a couple years ago (including decent PIMs and media players)
- X11 capability (if you know *nix then you know what I mean)
The only major cons I can think of is that the 3100 is heavy compared to the 5500 and price. It also means the 3100 feels less like a toy
Whenever I see my sister's 5500, I feel nostalgia, but the clamshells just blow it away.