I own an Ipaq and I like it as a gadget. But when people ask me for PDA advice and all they really want is an organizer I recommend a Palm. The single most important thing about a PDA is that you have it when you need it. It doesn't matter how many whiz bang features it has if it's sitting at home or in your car when you are out and about. Just looking at the dimensions you don't appreciate how much smaller and lighter the smaller Palm's are compared to the PocketPC's. But pick them up, hold them in your hand, put them in your pocket and you will appreciate the difference. Imagine trying to carry one around with you in the summer when you are wearing a t-shirt and shorts.

The Palm interface is also simpler and more task oriented - exactly what you want for quick data entry. The amount of free or cheap software for the Palm is amazing. The PocketPC's are more flexible, powerful and have a higher coolness factor but you pay for that with a more cumbersome interface, bulkiness and shorter battery life. The biggest negative of the Palm, IMO, is grafitti. I truly hate it. I don't seem to have the brain for learning a new alphabet. I do like the PocketPC's surprisingly good handwriting recognition.

I bought my wife a Palm Vx and I think it's a great machine for what she needs. The form factor is perfect. I wouldn't want it bigger or smaller. I also think an integrated screen cover that doesn't add bulk is important. You want to be able to throw the thing in a bag or in your pocket with your change and not worry about it. The Palm m500 fits the bill but I'm not familiar with the Sony models.

-Dylan