I was actually disappointed in Wal-Mart's selection. I saw the single burner hot plate, but it was a bit out of my price range and I've heard it takes darn near forever to heat coals on one.
I bought a coil single burner at Walgreen's for $10 and it works like a charm. It heats up my CH nats in about five to seven minutes. It cools down pretty quickly as well. This is what I bought
over at Walgreen's.
ETA: I have heard that with the solid hot plate style burners you can build a little tent around your coals with foil while they are heating and it will speed up the process. Let me see if I can find that video.