I bought the Zen Vision:M a few months ago and I am not disappointed. For a long time I was considering whether to buy an ipod or this. I have friends with the ipod and vision:m so I had used both of them before. In the end, I decided to go for this on price (at the time, it was about £30 cheaper than the ipod) but now I realise there are many more reasons why you should choose this over the ipod. These include the extended battery life, the radio and recording features and the fact that it isn't as restricted with the number of formats that it can play for both music and video. It comes with some good software which makes it really easy to install and use straight away. If you prefer, you can also use another media player to add music etc. I cannot fault the functionality of this product and even after I got it, I found features I didn't know it had. If you have heard people say that the touch pad is difficult to use, ignore them. It is so simple and you can change the sensitivity to your liking.
The only thing that you should be aware of before buying this is that it is VERY easily scratched. Be sure to buy a skin of some kind BEFORE you buy the player. Otherwise, you will be forking out more money to buy some scratch polish. I learnt the hard way! Personally, I use the invisible skin which is applied using water but if you don't want the hassle, get a silicon case.
If, like me, you are torn between the Vision:M and the iPod, get this. It has so many more useful features and you will not regret it.