Nathan,
Synthetic fill is very susceptible to losing loft after extended time in a highly compressed state. Medium grade (550-700 cubic inch/ounce fill weight) down is also compromised, but to a lesser degree. High end (750-900 cu.in./oz. fill – as is used in your Western Mountaineering Summerlite) down is also compromised but to an even lesser degree.
I drive my bag to the trailhead in it’s oversize storage bag and don’t stuff it until I’m ready to hike. As soon as I get to camp I pull it out of it’s sack and fluff it. In the morning I air it out and stuff it last just before I hit the trail. If I’ve got room in my pack and it’s not wet,I leave my stuff sack open and let the bag spill out the end to loft as much as possible. If it’s wet, I roll the opening of my drybag style stuff sack only 3 turns down to maintain as much volume in the sack as possible.
Having said all that, when I’m travelling light and fast with a small pack or carrying a large food load for a long, un-resupplied trip, I have no qualms about crushing the holy begeezus out of my sub 19 oz. North Face 900 cu.in fill Beeline 900, zipperless, 30 degree bag. I’ve been doing this for 15 years to my Western Mountaineering Ultralight 1-3/4 pounder and it still keeps me warm to 26 degrees.
My stuffsack of choice is the 8 liter ultralight, waterproof, drybag style closure Sea to Summit Ultra-Sil Dry Bag.<http://seatosummit.com/products/display/7>
It weighs 31grams/1.1oz. Fully open it holds 725 cubic inches. Opening rolled down 3x for weather protection it’s volume is 533 cu.in. My WM Ultralight crushed in the bottom with me kneeling on it to get all the air out and the sack closure rolled all the way down to the sleeping bag takes it down to 292 cu.in. And my Beeline 900 crushes to 221 cu.in.
Basically I buy top quality down, baby the heck out of my bags and crush them like there’s no tomorrow when I need to for as short a period of time as possible. This seems to work great for my bags.
Cheers, Al
