i've experimented in da hills w/ the only bivi sack or only lightweight sleepign bag and from now on will always go w/ the sleeping bag...the sack always ends up being colder, but then i've never unexpectedly been hit by a rainstorm.
No sleeping bag?
Fawk that shite.
The extra clothes you'll to keep your teeth from shattering will undoubtedly outweigh a nice, warm, summer bag.
Skimp on the clothes, not the bag. No sleep = shitty performance and a shitty time.
Here here!
What about those half-bags? I've heard some folks swear by them.