I must disagree - I think the new exchange
https://fbtcexchange.com/ is going to kick laggy campbx.com's butt. Easy to get verified, quick, responsive, lower fees (0% until August, then 0.45%) and the best securit features. In addition to google authenticator, let's you lock down BTC withdrawals to a small # of bitcoin addresses so even if you are totally compromised (they get your phone), they still cannot withdraw bitcoins.
It is even quicker to fund - for campbx easiest method by far is Dwolla. This is a quick wire transfer.
However, Campbx does have two advantages:
1. Cheaper to deposit USD (Dwolla charge 25 cents versus $10+ for a wire transfer
2. Located in USA so may have less issues with AML laws - they are already registered as a money exchanger