i guess there is only one that is better then yours little more speed and cpu cache.
they seem to be slightly rare.
I can't really find anything that would give me an idea of real world worth.
I suppose if you made a 10 day ebay ad, Then got on all the Forums, Apple fritter, Lem Swap, etc etc Made a decent post talking about it, and how rare it is (the same day you created the ad) so it can stew for a little time. Maybe get the word out a little.
took some nice pictures of it ... and it in operation.
Other then that you might spend the cash to make an ad, only for it to not even sell for 99 cents, because nobody is looking for it.