I've shopped with Pros Closet about half a dozen times, and paid around half what comparable auctions were ending at for similar items. Paid $40 for a Thomson Elite seatpost, and got my EC90 Equipe handlebar for $66. I've never heard anyone mention them being overpriced.

I've always found the auction-style listings to be very fairly priced. Their BIN-only auctions are often set a little higher than I'd like, but are still very fair relative to the rest of the market. They also ship lightning fast, which is just an awesome bonus.