1. Ability to transfer files between PDA and both Windows and Linux OS (but not between OSs).

That's a very new idea for a Palm. For instance the Zire 71 and prior doesn't do it.

2. Ability to view and minor editing of MS Office (Word, Excel, Powerpoint) and StarOffice docs on PDA.

Not really. It fails since there is no printer definitions to drive what the WYSIWIG will look like. Documents To Go comes as close as it gets.

3. Synchronise with my PIM, I use Mozilla not Outlook [again I had assumed I could install an app to do this, sales person said no]

You'll have to sort it out. What is supplied is documented at PalmOne.

- I don't know whether the above responses were due to a Microsoft-centric attitude in the store, or whether these are genuine problems, so I would be grateful for any views.

These are not problems. Just what you want to do and you get to figure it out. Even the PPC units will have similar issues.

- On a different issue, will a PDA function well as a music playing device, ie is it possible to transfer music files (mp3s as well as flacs, oggs etc) from a desktop PC easily, and keep a decent collection of music (+/- 100 tracks) on the PDA without limiting storage performance too greatly. If so that would save me buying and carrying a separate MP3 player (I spend a lot of time in the car).

Depends. Most don't get many hours of playtime compared to an iPod or such.

- Thanks in advance for any advice you can offer a PDA newbie.

My response may seem grim, but it's a PDA, not a file storage device and just recently they added MP3 playback.