PC is durable, really hard to chip, but the finish isn't as smooth or glossy as paint. Around here, at least, the shops advertise a wide color selection, but when you show up, they tend to have 200 shades of gray, plus safety orange and day-glo green. Last time I got an estimate (a year ago?) I think it was $125 if I took in the frame and fork with everything removed. that price included stripping, shot-peening (or whatever they do for prep), masking and application of the stuff.
It's worth calling around to find a shop that's done it before. I tried three. the first two just said, "Sure, we can do it," but the third asked intelligent bike-specific questions, like would i remove the BB fixed cup and whether the frame was lugged.
As it turned out, I had to buy a new water heater and put off the bike (it's a singlespeed I just rat around on in bad weather). But over the winter, I'm going to go for it.