350 FPS v2 mechbox (PDI 150% as I recall) in -20-some weather (broke on the first shot after being in the cold for a while):
Mind you I was able to play with it all day, I just had lousy FPS :P
The colder it gets, the more problem-prone everything becomes: frozen/ripped hopup sleeves, accelerated battery drainage, increased risk of damage to certain materials, etc