After long deliberation between the options we have got a 'Babybay'. My understanding is that it will last longer than a Moses basket but obviously isn't a full-scale cot. With the babybay though you can buy additional pieces to convert it into a little chair or playpen later on, and otherwise the resale value seems v. good - we bought ours on ebay.
Reasons I went for the babybay in the end over other models - I preferred the wooden rather than cloth design, I liked that you could get the fourth side for it so it can be stand-alone if you want, it does fit flush to the bed and as well as varying the height to match your mattress (ours is quite high) it also has a bolt to lock it securely to the bed-frame (which a lot of them don't). Space was also a consideration for us as we don't have loads of room around our bed.
Possible drawbacks - the distinctive shape means you have to improvise a bit with cot sheets etc. Though we were lucky and the lady we bought from on ebay threw in a set of sheets etc she had made herself to fit. Ours also came with both the fourth side and a set of castors, both of which I think you usually have to order separately.
Searching for 'bedside cot' and 'bedside crib' on ebay is actually quite a good way of getting a sense of the range of models.
Baby not yet born so can't report back on using it! It looks nice though.