Use Cryptsy we just celebrated our 3rd Birthday, and still going strong! You can buy numerous altcoins as well as Bitcoin.
sometimes deposits are too slow there(and withdrawals too), it's that fixed already? because despite this there is a huge volume which make cryptsy an interesting exchange for moving big amount
If your verified you have way less delay in moving your coin in and out. Most deposit and withdraw delays are security and compliance flags kicking in.