[sourdough]

The point about 2 smaller tents is on the money. Depending on where you're going the ability to put up a mega size tent in a decent spot could be very challenging.

On the tents, you get what you pay for. If you think you are going to be in inclement weather you will be wanting to pay a little more or spend a lot of time in wet sleeping bags. Been there, done that. Took a trip to Yellowstone camping out. Wanted a big tent, as you do, and went to the local outdoor store. Got the biggest tent they had, the guy said it was a very good tent (don't remember the brand) but it was $200+ back in the early 80s. Outside of Grand Lake? in CO we were in a campground and a pretty heavy rain came. Every seam leaked, the floor was covered in water, the sleeping bags were soaked etc. etc. etc. We spent the next day, supposed to be traveling, in the little town in a laundromat drying everything we owned. Just be aware.
I've seen other, cheaper, tents literally collapse from heavy rain.