1. Your oil temp will be ambient temperature when allowed to cool long enough. The gauge doesn't start registering until it heats up past 140. I try to let the car warm up before I really get on it, but there have been plenty of times I didn't let it properly warm up mainly because I live adjacent to a 60 mph highway and it's a right turn with no merge lane.
2.
I often do the same because, to me, that's really where the car feels like it wants to be. Also, for a DD, it's close enough to power band that you can get up easy, and engine braking is sufficient for most non rush hour traffic situations. I recently learned Nissan recommends shifting into 6th gear at 33 mph so I've been having some fun with that
But of course 7300 RPM shifts are fun, too
3. I didn't notice anything, but I didn't get too nuts with the car during the 1200 mile break-in period.
4. It's all in how you drive it. As a DD I get well over 300 miles almost every tank, but I have been as low at 180 and high as 405. I also empty nearly all of the 19.1 gallon tank. Spirited driving and track time affect this tremendously.
5. With proper snow tires and driving skill and knowledge, absolutely
