Last year I switched from Muck to Dry Shod...About the same price and they were touted as being more comfortable. And they are. Dry Shod was started about 10 years ago by the same guy that designed and started Muck Co.. I just have their regular farm boot, but like I said it is more comfortable than the Mucks,which I wore for years. Dry Shod makes a heavy cold weather boot.
As far as sweat, the Dry Shod are pretty good to a point...better than most. But with any rubber boot, if you have trouble with sweaty feet, eventually they will sweat.
And the nice thing is there are no rubber boots still made in the US (at least that I could find, and I searched hard), so you don't have to worry about if it's made in China....all rubber boots seem to be!