I am using underquilts and top quilts ordered from Undergroundquilts.com. A recent trip to northern Michigan in December was a true test for the gear. The top and bottom quilt provided more than enough warmth down to a damp 22 degrees. The construction is well thought out and the quilts are easy to use with adjustable cordlocks, snapping footbox, etc.
I would reccommend the gear to all hammockers; quality designs and construction, better than competitive pricing, and top notch customer service.
Check them out at www.undergroundquilts.com