The Lake 302s are the warmest cycling boot that I have worn. I don't size up and still have room for double socks. These are good down into the Twenties F., maybe a little lower. These stay pretty dry even though they do not have Gore-Tex. The soft toe is nice to have when it's cold.
For warmer temps, say ThirtyF to FiftyF I like the Shimanos. Size up at least One full size. They run small.
I've also used the Pearl Izumi Barrier boots. They are good to about ThirtyF as well. They run small too. Not my favorite.
Neither the Shimano or Pearl Izumi shoes are good much below freezing IMO.
Below Twenty, I go with Neos overboots and platforms.