I've had this player a couple of weeks and think its brilliant.
My Zen vision M, begun to have some problems after 18 months of use, so I decided to upgrade to this player. The X-Fi cyrstal sound and 3D experience is a really good feature and brings out the full music experience you deserve after paying nearly 200 for this player.
The headphone which come with this player are not your standard Creative one's, instead you get one's which can handle the bass etc much better so there is no need to buy extra headphones.
This player can get very loud, a lot louder than my previous mp3 player. With the X-fi on, I don't think i've heard better clarity in music. I haven't even tried it with the bass on yet as its so good.
The 9 buttons are not as good as the scroller on the Vision M in my opinion, although they do the same job. Some people may prefer this method as the scroller was very sensitive.
The only downfall I can see for this player is that you will need to convert AVI (movie) files for them to play. I don't t know this is, its seems as though Creative have gone backwards not forwards on the video front!
Overall a decent player with the X-Fi expansion a really good feature.