I've got one - been using it for 6 months or so. No real problems with it - the audio alarm on slows is a bit quiet. Sometimes takes a wee bit of patience when trying to call up logs for previous dives though
<font color='#000080'>I bought a second hand one about a year ago - no problems with it. It's fairly simple to use under water (i.e. you don't need to do anything) but above water the contacts can be a pain (easily fixed though - rub them with a pencil eraser, sorted).
I've got the PC interface for it, which makes it all the better (so I can download my dives and look at the nice ggraph).
It's not as 'fully featured' as newer 'puters with changeable gas mixes and RF contents gauges, but it's a lot cheaper, it works and it's configurable to give a more conservative ND limit (using the altitude setting).
I've got the manual in PDF format somewhere, drop me a PM if you want it to help in your deliberations. I've also seen the instructions for a home made PC interface on the 'net somewhere, if the one you are thinking of buying doesn't come with one.