These look like what I bought:
The price was pretty similar, and seemed like a decent deal. I like DIY stuff, but these looked like a bargain. There is no heat setting on them.
When I removed the flask and let it cool and settle, there did seem to be quite a bit of yeast in it. I put a piece of tile on top of the magnetic stirrer, and then an aluminum pan on top of that as a heat sink. I set the flask on top off all this after it had cooled. The stirrer still worked, so I left it running that way last night. The flask was cool this morning when I checked it. I will decant the "beer" and add fresh wort tonight, and see what happens. I still hold out hope for using this yeast this weekend.