PayPal = Caviat Emptor
I've never had trouble with them, but other than five items on ebay, I've not dealt with them.
There are literally thousands of horror stories from former PayPal users. Everything from misdirected funds (which is about 50/50 for whom to fault) to things like "account shut down due to suspected fraud" when a vendor has a sale that increases traffic by 200-300% in a week.
With the right setup, you should be able to direct transactions right to the client's business account and avoid the middle man.
I spoke with a paypal manager, she said even large transactions like $10,000 will not be blocked or held up if you are completely verified. the problems are when paypal users start transacting business without a business account and receive large or frequently large ongoing payments, on a personal account or premiere account and don`t get full verification, 2 payment codes to their savings account that need to be entered into their paypal login, verify address with mail and phone number. but obviously I don`t know every case.