Bought a couple of things of
ebay last week and thought I would share the experiences:
First, I bought 3 Proof cents from a seller, a 1956, 1958 and a 1959.
I got my package last week and in it there was the 1956, the 1958 and a 1962 instead of the 1959.
I wrote the seller and told them the mix up. They were very polite and told me that some of the '62's had gotten mixed in with the '59's and they would send out the '59 asap and to keep the '62 as a bonus.
Cool, right?
Today I received an envelope from them with a paper inside that had "sorry for the mix up" written on it with a 2x2 taped to it. Inside the 2x2.... another '62 proof

I wrote them and told them they had done it again and am waiting for a reply.
The second transaction was a more positive one:
I ordered a 1965 sms cent from a seller. I paid immediately then noticed the next day that the listing had been removed from
ebay with no explanation. I wrote the seller and asked to make sure I would get the coin and never received a reply so I started to get a bit nervous, granted it was only a $2 coin, I still want what I pay for.
Today I received a package from the seller, not only was my sms cent in there he also included a BU Birthplace cent, a BU formative years cent, a BU 1975 cent still in mint cellophane, a 1987 proof cent and a 2000 proof cent all as a bonus.

My only regret now is that the
ebay listing has been removed and it doesn't even show up in my items won section so I cant leave him some awesome feedback. I think I will shoot him a message with a big thanks.
Anyway just wanted to share a couple of good and bad experiences with everyone. Thanks Everyone!!