I've bought from them, both film and an Xpan. Solid experiences.
Purchased via eBay, good experience overall.
Items for sale or trade at www.Camera35.com
I go to the Harvard Square store every now and then, because it is nearby. It is small and limited selection, but sometimes they have what I want. There's usually some film there, but the store price is higher than the online price.
blog: The Institute of Impure Science