It's a good deal if it's in like-new condition! I'd get it...you can always unload it back onto CL for about that price. There is usually enough demand for the Pista.
I do think that it comes in fixed gear only, not singlespeed. I've *heard* that you can screw freewheels onto fixed hubs, but there's the danger of stripping the thread. You'll have to look into that if you're serious about the bike and don't want to spend any money on another wheelset.
Lastly, there is always the track geometry discussion. I don't own a Pista so I have no idea if the comfort issue is blown out of proportion. Again, something to maybe look into.