I don't sell chips as a rule therefore my opinion might be a bit more unbiased.

Ebay's chip category is ladden with a lot of trash to weed out.
Ebay in general doesn't seem to care if fakes, fantasy chips, trays etc are sold. If you read the various threads posted by other club members you will note they have been unresponsive.

Jackpot on the other hand is run by club members who support our hobby.
I think the choice is clear