I found it very useful for killifish eggs, the only category I ever checked. There were credible sellers and results were good. Recently, there has been some price gouging appearing, with ludicrous starting points for an egg auction. So much can go wrong in the mail with eggs.
The AKA had pretty well abdicated any egg sales to Aquabid. But they've been pushing to get people to list on Mark's site, as Europeans weren't sending to the US anymore because of the laws. If the AKA can step in and run proper auctions with a code of ethics, it would be good. I wouldn't be able to use the resource, as all the eggs US friends have sent me over the past 5 years have simply vanished, probably snagged by US customs based on the electronic forms. But I would like to see my killiekeepig friends in the US get back to what once made them an important organization in the killieworld.
There are always workarounds for people like me who know the ropes, but for new aquarists interested in some of these fish, it will be harder if Aquabid dies.
Things run by individuals rather than things run by motivated groups are always unstable and vulnerable.