WM5 does fix the whole problem of battery-dying-erases-memory (and don't forget pda-crashes-kills-battery-erases-memory) but that's just about the only notable improvement among a whole lot of drawbacks.
I'm specifically talking about going from a Dell Axim x50 to an x51. The story is slightly different from vendor to vendor.
Things I've lost in this upgrade:
- A2DP stereo bluetooth audio (I'll admit it was a hack on the x50)
- Embedded visual basic (my public transit app won't run on the x51)
- Bluetooth network profile (can't use bluetooth access point now)
- Bluetooth mono headset profile (no more wireless voip)
- Activesync over TCP/IP
The x50 is already long gone or I'd attempt a downgrade...
Ok... one more gripe and I'll move on. Exchange sync would be perfect on the Axim if only there was a checkbox for "private" appointments. Doing planning through my ppc is pretty lame when I have to remember to log on with outlook to make things private on my shared calendar.


