What do you look forward to after a long day on the trail? Food and a good night's sleep probably. But if the food isn't great you forget about that by morning. If the sleep isn't good, you'll feel that for the rest of the day. So invest in future you, put together a sleep system that will keep you warm and comfortable all night long. This is the place to splurge on the weight, get a pillow and some top of the line insulation. Decide what materials work best for you, and find the right temperature range for where you are. Whatever you do, please don't cheap out on this, you'll hate yourself later when you buy a second set of new equipment to fit your needs better.