I've really learned a lot from reading this forum about options out there for lightweight backpacking tents, but I've yet to see much information concerning 3-Season vs. 4-Season tents. I'm planning on a first season rifle hunt in Colorado next year (5 day season in mid October) and plan on hunting and camping in the 9000'-11,000' range. I've read that some consider 3-Season tents adequate enough to handle the occasional snowstorm but I also know that the nights can get down in the single digits while the days can get pretty warm too. Is the extra shelter provided by the 4-Season tents necessary or would I be better off with the better ventilated 3-Season models? Since I only want to buy one tent, can anyone share their personal experience with either or both kinds of tents at these elevations in mid October in Colorado? Right now, I'm leaning toward the Big Agnes Fly Creek UL2, but can switch my search to a 4-Season variety if you all persuade me. Many thanks!