damn dude... 221 stable? that is good stuff! I have no idea how long mine would last, but maybe today I will give it a shot.
How cold is the liquid pumping? I dont get lower then 13°F pumping it through the 295's and the CPU.
ALso lucky for you the humidity is quite low.. its a fine frost on your block. If it was more humid, you probably would have more problems, but im guessing around 40-48% humidity?