I have owned my Zen for just over a year now and have had no problems with it at all. It is easy to download music to, using a piece of software called Zen Media Explorer. This enables you to manage your music, rip audio from cd's, browse media and create playlists from you pc.
The display is not huge at 1.5" but is plenty big enough. The Zen is lightweight and the battery lasts for about 15 hours before requiring a recharge.
Also built into the Zen are a Organizer: Calendar, Contact and Task list, but to be honest I am not sure that these apps are all that useful. In fact I have never used any of them as my mobile phone has all these functions and performs them better than the Zen does.
It does however hold 25-30 albums with ease and has an intuitive interface for you to select the music you want to hear.
So if you want to get an mp3 player that is a bit different and you dont want to spend a fortune you wont go far wrong with a Zen.