Gimp, for rubber boots, I've used the 800/1200/1600 and this year I bought the 2000 Alpha Burly, which I have not used as yet.
What I can tell you is even when I wore the 1600 insulated boot my toes got quite coldduring extreme cold weather here. I added an insole and it helped a whole lot.
I'm yet to knowhow the 2000 will work this year.
I was however really tempted to buy the Mock Woody Max, as I've heard good things about them, but I've not used them before, unfortunately.
I find the Burly's to be quite acceptable in weight, asit's hard for me to wear a boot that's heavy.
I heard recently about the Cabelas Inferno, a buddy of mine got himself a pair and said he immediately felt the heat when trying the boot on, just another boot to look at.