What weight penalty are we talking about? You're going to make sacrifices to go lighter in a ground shelter, too.

Let's see. Two three season, 20 degree setups, both currently in my possession:

Hammock 24 oz
top quilt 20 oz
neo air 13 oz
silnylon cat cut tarp 13 oz
lines/stakes 6 oz approx.

Hmmm...

Sublite tarp tent 24 oz
neo air 13 oz
top quilt 20 oz

Not a huge difference, really. Only in comfort. The hammock will automatically win that category every time. It will also be more comfortable and keep me drier in typical three season weather for my usual destinations, ie rain/light wind.

I could easily get a lighter hammock, possibly a lighter tarp - could knock some ounces off by swapping from MSR groundhogs to something that doesn't hold as well, or by switching to a cuben or spinn tarp. But we all strike our unique balance between budgetary concerns, lightweight, and comfort. For my purposes, both of the above are huge improvements over the 4 lb dome tent, the self inflating (uncomfortable) thermarest, and the 30 oz 50F (labeled 30F, totally not accurate) sleeping bag. The top quilt is accurately rated to 20-25F, and I've had plenty of subfreezing nights to claim it.
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