The critters arrived today, most of them in a big pile in the styro cooler they were shipped in. There were a dozen small pastic containers, most of them empty, but with the lids still on. Maybe the snails got out then the lids snapped back into place in handling? In any case they're temporarily situated in a large plastic tub with fresh water, some sinking pellets, and a sponge filter. Some of them haven't stirred yet, most have moved around or at least poked out their heads, and a few seem to be eating the pellets.
I ordered 175 and received 2 extra, bless the selller's little pea-picking heart. It remains to be seen if there are any DOA's.