own a gear drive DK55c - and use it in temps below -20 w/o a block heater. it sits outside and never had trouble starting this winter. as folks pointed out, it needs to warm up. kiotijohn's approach is perfect.
in general, i typically let the tractor warm up for at least 15 min. before i use it in all temps (and pray that the heater in the cab comes to life sooner rather than later).
i beat the gear drive vs. HST issue to death for a LONG time. as pointed out, it comes down to preference and usage. i'm very happy that i choose a gear drive and would likely stick with the same choice even if i could get the DK55 with a HST at the time of purchase.
pf
