I have had about 14 Palms over the course of the last 10 years. I currently have a Palm Tungsten that I've had for 4 years.

I briefly tried a Treo, but found that it's phone features were stripped down, it's pda features were stripped down and the size wasn't well suited to my needs.

If you're just looking for basic calendar/phone book functions, I recommend you get a low end model. If you're looking for spreadsheet capabilities or a lot of add on programs, you'll need the memory offered by a more expensive model.