Well, I've been buying and selling on Ebay for around 10 or so years, but mostly vintage dinnerware, with the occasional electronics or camera sale when it was time to sell my old items. The thing is, I rarely buy any dinnerware anymore there, since at least 50% of the time now it has undisclosed damage (chips, cracks, scuffs) that completely devalues the piece. Unfortunately, all of the other collectors out there have figured this out too, so now if you are an actual GOOD seller, you can't get the correct value for your items since buyers won't pay premium prices for anything on Ebay (since they assume it will have hidden damage)....I've gone to selling my dinnerware to a private group of collectors through a message board and a couple of Facebook groups instead. It's much nicer and easier all around, although it is a smaller audience than would be reached by Ebay (but oh so much less hassle...).
I've mostly had pretty good experiences selling electronics and camera stuff with a couple of notable exceptions, but the level of fraud that is going on now has gotten pretty high, and I can't really afford to risk that. Ebay does NOT give even good sellers the benefit of the doubt, and that is a real problem. Buyers have learned they can beat the system and scam their way out of paying for their goods by using the "buyer protection" feature, and it's just gotten too iffy to sell there anymore (plus the cost is just insane now).
I have not sold the GH3 yet, though, so I may have to list it there at some point...I'll give it more time though... Thanks all for your comments!