Warm weather extremes? A friend of mine has a old Moss 3person version of this tent that she uses on the Black Rock dry lakebed in Nevada. We've seen temps above 105, and the inside of it gets steamy and stuffy, but livable. Doesn't really have much for ventilation.

She sticks with it, because it will shrug off a 55mph dust storm that flattened most the rest of the tents.

Hopefully this will answer some of your questions:
A) This tent is almost identical to the Moss Little Dipper, one of the strongest and most weatherproof tents ever produced. The reason I mention that is because of the guy-out loops it used and which are also used on the StormKing. They allow you to use cordage, or for the absolute worst conditions, climbing rope up to 11mm. There are three separate guy-out loops on each side of the tent that can be used to anchor it down. There are also several more throughout the fly which are pretty obvious and have reflective piping making it easy to find in a white-out.

This tent is very taught and is very much snow worthy. For a five man tent, I don't think you'll find anything more snow load proof. It's huge hooped vestibule will swallow up the largest packs and winter gear and everything about this tent screams winter! As you can see, it only uses pole sleeves, not clips, for the best pitch possible. The floor is super durable and has a 10,000mm coating, one of the best in the industry.

B) This tent is fully capable of experiencing the worst weather right out of the bag! All the seams are taped and it has gone through rigorous testing before it's shipped off. The only thing I would suggest is setting it up a couple of times before going out. This will help you get familiar with it if the weather gets bad or if you run out of light. It really isn't that difficult to set up, but with seven separate poles, it is more challenging than a 3-season tents.

There are very few tents that compare to the StormKing!

Included are 10 GroundHog II Stakes, a descent roll of guy out cord (not enough to completely guy it out, but enough to anchor the fly to the ground), a full-cover fly which includes a hooped vestibule, but no footprint.

The only thing you will need to buy (other than the tent itself) is a StormKing Footprint from the items on your list.