Well, today we had our coldest morning of the season. The dash display read 8°F when I went out to the car. After 30 seconds of preglow (light went out after 10 seconds), it fired right up without a problem. The idle was a little rough for about 5 seconds, but cleared up almost immediately. I was expecting a fuel gelling problem or something of that nature, but it started on the first try without incident.

The SDL doesn't have the block heater cord installed, as the car is originally from Texas, so I haven't tested it out yet. The block heater on my 190 kept things nice and warm all night, and it would start like a champ in the morning. If your car has the cord installed, just plug it into a standard 110v outlet for an hour or two before you're ready to start the car, or leave it plugged in overnight.