I have the X30 High and see no reason to get the X50, or now, the X51. The X30 still has the fastest processor (624MHz), standard RAM (64MB), wireless connectivity (Bluetooth and WiFi), and approximately the same battery life. There are several things the newer models have, but nothing I can't live without:

* The new design is great, but it's what's under the hood that counts, and the X30 doesn't look that bad compared to some other models.

* Although it lacks a CF card slot, SD is just fine. The only catch is that the cards cost $10 more, on average.

* The 128MB-256MB ROM is nice, but a storage card is just as good.

* The X30 cannot be upgraded to Windows Mobile 5.0. However, the newer models won't take advantage of some of WM5's best features, including internal hard drives. Thus, the only advantages are new versions of Pocket Office and ''persistent memory.''
- I use third-party office applications anyways. (They are better than the latest version of Pocket Office).
- Even with persistent memory, you still need to make backupps in case something goes wrong or the unit becomes damaged/missing.
- Even with persistent storage, you still need to carry an extra battery to continue using the PDA. (A car charger really comes in handy when using GPS.) Thus, if you have constant power, why do you need persistent storage?

Finally, I see the X50v/X51v's VGA screen and graphics accelerator as great features, but not something that's needed unless you are really into graphics. In that case you'd probably be better off with a portable DVD player and/or a PSP.

All said, with a few customizations (I installed several programs, skinned the interface, and tweaked the registry), the X30 is just as good as the later models, but at a fraction of the cost.

Hope this helps,
John