I usually don't buy off of E-Bay, but I am trying to complete my Mobile Fidelity and Nautilus LP collections and E-Bay has had alot of the titles I needed.
I must be lucky because over the past 6 months I have bought probably around 100 LPs and all of them have been perfect, (or at least the condition they were listed). I haven't purchased any regular records, so I can't comment on those sellers.
I also try to buy different titles from the same seller.
Some of the packaging has been horrible, but the LPs arrived okay. I just don't get some of the sellers lack of proper packaging...it's not rocket science. That's my only complaint, so far, about buying on E-Bay.