I currently use a West Bend Crockery 6-quart stainless steel cooker. I actually am not too thrilled with it since it seems to cook REALLY hot. I can have it on KEEP WARM setting and it seems to fry everything!
I used to have a Rival (I think) that we got as a wedding gift, and it was the best. It had the removable crock (as I think most do nowadays) but I put it on the stove and it burst!

I really miss that one. Then I had one that dh's mom gave us for Xmas one year, and I didn't like that it only had 4, 6, 8, and 10 hour settings, with the 4-6 being high, and 8-10 being low. I wanted one that was just low and high, and you could decide how long, kwim?
Aah, I know, I am being too picky, but when you want to cook a lot in a slow cooker, you gotta be choosy!!
Anyone else?