There's a reason why their rates are so good, and it's most likely because their funds come from either fraudulent sources, or that their paypal accounts are somehow tainted in the past.
Which is the probable reason why people are complaining about their service, as others have mentioned in this thread:
No one in the exchange business with clean funds with a clean source will ever give you a markup (of $400!) when you sell your BTC to them. There's a reason why accounts are getting limited. Furthermore, Paypal is intrinsically risky due to the nature of chargebacks. You simply do not want to deal with them, period.