"Best" is subjective. I will say that I love the Sky Commander and prefer it by a large margin to the Tangent style DSCs (Lumicon/JMI/etc.). But that's just me.
The best one on the market is Argo Navis, because Argo Navis will measure errors in polar alignment, and in the actual machining of your mount (among other things), and compensate for them.
The others are just the others. Both work. If you're using a wide field refractor it won't matter unless you want to get into imaging and land on a chip. Accuracy with regular dscs tends to be around 20 arc minutes pointing error. Accuracy with argo navis will be 3 to 7 arc minutes depending on your system and the number of stars you feed it.