I have one that I use as an MLT for brew-in-a-bag. It can do 2 1/2 to 3 gallons. I just heat some sparge water on the stovetop to rinse the bag. I picked it up off Ebay for about $75 new.
I strap a 5 gallon paint strainer inside the steamer/strainer that came with it, and once I pull the grains, I can use it as a boil kettle. Can't really boil more than 2 gallons though without covering it with the lid. Once I achieve boil, I can partially crack the lid, but if you uncover it totally, you'll lose the boil. I think the element is only about 1200 watts or so.
Getting the aluminum kettle out of the housing to chill in the sink is a little awkward, because you have to tilt the kettle to clear the drain spout on the housing, while avoiding spilling the wort. Not impossible, just awkward.
As others have said - forget about the temp being accurate with the dial. My experience is that it's at least 25 degrees off on a mash. I just use it to maintain temps.
The setup does work OK though for doing step mashes, but you've got to stir like crazy & keep from getting hot spots.
Look at the "Similar Threads" below - and you'll see more than a few people have tried these with varying success.