Current is not power. Power is voltage times current. So to make a certain amount of power at 2S takes three time more current than at 6S. You can't tell just from the ESC how much power you will get. It all depends on the motor and what you do with it. I looked at both of those ESC's. I can't even find a current spec on the Sidewinder. They do suggest a suitable motor. Full specs can be hard to come by with these RC products and I have a tough time figuring it all out.

I was asking some similar questions about 6S vs 4S in an 1/8 scale truggy. Most of the real race ones are setup at 4S but the RTR ones are coming out with 6S. These 6S RTR's have 2300kV motors while the serious racers are running 4S at 2200 kV. For realistics 6S operation you should drop the kV down to something like 1500 but Hobbywing doesn't sell 6S 1/8 cscale motors with that low a kv. Tekin does though.

I just put an HW Xerun combo in my Losi 8ight E. They have a longer motor for truggies. Both are about 2200kv. So I will run 4S. Although you can run that motor at 6S and gear it down some, it would be insanely fast probably. So I guess you should think about the HW combo and run at 4S. Unless there is some reason to stay down at 2S, you can make the power with less current and heating at 4S. Run 6S if you want but it may be super overkill.