I have a Palm E2 and have a friend with a TX.

E2
+ Pros
-pretty good battery life
-seamless integration with outlook (I use the calendar function a lot)
-works pretty well for MP3's-if you want to use it like an ipod, buy pocket tunes

-Cons
-small onboard storage (have to use SD card)
-first one I bought had a broken bluetooth adapter (returned it for a replacement)
-had a problem with the speaker for a while (fixed by tapping on the case-it hasn't been a problem since)
-to access internet, have to use a card that fits in the SD slot, it sticks out (can't use hard case) and is a HUGE battery hog (I get about 25-45 min of wifi on a full battery charge depending on what I'm running)
-after a couple of years of use (2) the screen now whines (imaging high pitched noise) due to the touch screen. I normally doesn't bug me (~90% of time that palm is on, I use it to play music through headphones)


TX (not mine, but have used a friend's)
Pros
-integrated wireless
-same outlook integration
-decent battery life (with wifi OFF)
-faster (opening apps doesn't take as long as E2)
-more built in storage space than E2

Cons
-Wifi drains battery quickly (but not as fast as the E2)