I won't even escrow sales that involve paypal. If you accept paypal it is only a matter of time before you get burned, escrow or not.
You could wait the 180 days it takes for charge backs to expire. I don't think the average bitcoiner's going to want to wait half a year for their cash though.
Unfortunately that is not sufficient. Even though it is paypals time this system can still be tricked by paying something with paypal and paypal charging a credit card.
The user then can do a chargeback with the credit card after 10 months or so, in the US, i believe, even longer.
So even that waiting time would not be enough.