I wouldn't have refunded until a little further down the track.

People that call members scammers are often the scammer, especially if you are polite.

You can have the reply removed as it mentions a dispute which is against the rules. Point that out to ebay.

To anyone half intelligent, it's not you that looks like the bad guy anyway.

Doubt it will effect your account very much and it will soon be on page 2 by the looks of it.

Hold you head up high and know you provide a very good service.