I recommend Virga Outdoors, but of course I'm biased :) ;)

Here's my latest design (this one for myself)!

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=73796

http://www.facebook.com/media/set/?set=a.315133415256700.50718.126284534141590&type=1

Get an EE 40F quilt revelation.
Have Tim do lighter straps,like used to. the ones he is using now are too heavy IMO, a step in wrong direction.

You should be able to get it about 15 oz

Wear your baselayer and midlayer when you want to go down to 30, maybe add down booties 2.4 oz below 35F. THats when my feet get cold in mine.

You dont need a real hood over 30-35, a beanie and hood on a fleece or such is plenty.
If you want to go lower into high 20s add a goosefeet/zpacks down hood too, another whopping 1.2 oz.

You can push it to about 25F with these items and your puffy.
Very versatile too.

And MUCH roomier than summerlite, highlite, etc.
It works MUCH better at 55+ too than those bags as well, sans hood and down socks.

Or, get overfill and it ought to be better to about mid 30s by itself.

Edited by livingontheroad on 02/21/2013 19:43:13 MST.