I'm not sure how cold it gets in Montana but up here I am loving my new autostart! I had a block heater installed but hardly ever plug it in anymore (I try to remember but it only gets plugged in like once a week) I don't really notice a difference wether it was plugged in or not. It was pretty inexpensive for it to be installed though. For oil I use 5w-30 in the winter and 10w-30 in the summer. I use all synthetic fluids, and encourage everyone to do the same.
However with the autostart and warming it up every morning, during lunch, after work, and whenever else I am only seeing 10 miles to the gallon. I use 92 octane and am supercharged
2001 Ironman Daily Driver... 3.5" suspension lift (OME912 springs and 1" spring spacer), ball joint flip, 1.5" front diff. drop, 33"x12.5 TrXus MT, 16x10 Eagle Alloy rims, Interceptor, PV muffler, K&N air filter, Alpine Supercharger, Bilstein shocks, and some trimming.
2000 Ironman Project LS-1 VX... very slow progress but someday....... ohhhhh someday......