It's a great bike. A couple better components than my 06 Roubaix Comp and a slightly better frame. You may want to know that this bike came with the FSA SL-K crankset with 50/36 rings and a Shimano 12-27 cassette. That's what I have, and I love the gearing. However, you won't have the same climbing gears as a more common 34T compact small ring. I don't know if that's important to you, but I thought I'd throw that out there.

I don't think that's an exceptional discount considering the age of the bike, but it's definitely better than anything new you'd find in that price range. I'd see if the owner would let you take it to a shop for an inspection before you fully committed, since the frame and cranks are carbon and it is over 2 years old. Barely used doesn't necessarily mean really well cared for. If it's in good shape, go for it if it fits you.