For hardcore riding nothing from the sled world can compare for support, balance, and agility of the HMK Pro Boa Focus. Staying dry is a matter of keeping your gator down and most critically making certain that you start your day off completely dry (obviously an exposed hole doesn't work either!). We ride multiple days with no breaks and if you started with sweaty or wet boots they would always be damp. Light socks, good fit, gator down over the tongue (high waters and stomping around getting snow rammed into the tongue is a recipe for the swamp...they are warm so sweating can also be an issue), and some people with very sweaty feet need powder. Do this and make sure they are dry to start with and you will have great performance from the HMK boots.
Another option for 2009-2010 is the new HMK Voyager boot. Waterproof and breathable lace up boot that appears similar to the Klim GT. I have all of these above so we will get a chance to test them in few weeks as our riding season gets rolling.
When making your purchasing decision you have to consider the actual style of boot you want as well as the brand.