When I connected ZEN to my desktop PC with XP – no additional software required to manage the files on ZEN.
Then, when connected to my laptop with XP – no such luck, had to istall software from CD supplied with ZEN.
Guess it really depends on the vintage of your XP (namely, drivers library).

ZEN menue and buttons configuration is as easy as mobile phone-which is good on the move.

Buttons are responsive, except the one in the middle: when that one clicks – it means nothing, you still have to press harder to get the result. However, if you push too hard it will trigger twice and you overshoot the target. This is espesially destructive when you are on the move.

After buttons are pressed, there is no lag you would normally see on your mobiles here and there – ZEN updates momentarilly (but note – I did not try it with full 32GB load).

The best discovery: It has searching capability where I could find a track/artist/album/… using a keyword. Although, to type the keyword you have to navigate an on-screen keyboard (on mobile phones you can type whole message without even looking on screen!).
And, it seems to me that you can not search tracks and artists and albums in one go, like you do it in Windows Media Player, it only allows you to search withing a separate category. The manual on the CD says nothing about.

NOW THE MOST IMPORTANT (for me) – The quality of sound.
Before buying ZEN I was reading ‘professional’ reviewers, who proclaimed ZEN sound as excellent. Those guys were talking about clarity etc.
They did not mention how they tested the sound, except the names of the songs they tried on ZEN (probably through the earphones). Well, when I plugged ZEN to my in car system MONDEO Ghia SONY, the three things became obvious:
1. Sound quality is far inferiour to even my Toshiba laptop that has only onboard (cheap version) sound card: when I plugged ZEN the subwoofer had nothing to play – no bass signal, then I plugged my laptop (headphones output) – and here subwoofer comes!

2. ZEN has equalizer and the bass boost options which I thought might deal with the problem of the bass sound. The bass boost was almost not perceptable. The same with the Equalizer, except the DISCO option, which makes bass richer, but not enough to compare with my (same cost) laptop, not enough to hear the subwoofer. Plus, with the DISCO filter you get perceptable bad distortions in the upper bands, which altogether, on high volumes (car system volume) sound like old radio (girls will kindly ask you to switch it off). This never happened with my laptop plugged in.

3. ‘Profi’ said ZEN is loud enough. They ment enough for earphones. When I plug it into my car stereo it is not enough. The laptop has 3 times volume of ZEN. So with ZEN i have to put my in car stereo volume 100% – and it was not that loud. Now, if you use it in your car, be careful to switch off you traffic alerts off, cause if you listening to ZEN at 100% volume then the traffic alert comes in at 100% loud, when you didn’t expect it – you may want to jump out of the car right then.

Overall, I liked it a lot as a earphones player, but I hated it as my in-car music. For that reason, ZEN, you are fired.
I wish I could return it to Play.com, but I have it unpacked. If anybody interested, I would give it up for 20 pounds less.