Biscotti, I quite liked it (Costco) and I'm not even a big 'buy in bulk' person, but we did get some good bargains, like cleaning products 4x spray and wipe/ajax bottles for under $10, that sort of thing. Toilet paper was cheap in bulk and proper brands like Kleenex etc.
I was quite partial to the Yoghurt there and garlic bread.
DH is a big 'researcher' when it comes to buying anything of value and he bought a Sony digital clock radio for about $50 cheaper than JB Hi Fi, so if you know your prices you can get a good deal. They even sell diamonds!
The meat was good, as was the party stuff and we thought we got our $60 membership money back in what we bought. If anything, it was certainly eye opening to see how much stuff they would have in the one place and the trolleys are huge!