>>495671>poly or nylonI've only used nylon, but poly apparently has less stretch and a different feel (less soft, more smooth). Nylon is more durable and has a higher weight rating. Nylon's been great for me.
>10ft or 11ftHow tall are you? If you're tall (>6'), you definitely want an 11'. Longer will almost always be better anyway: the main disadvantage that I've noticed is you will need more space between trees. If you are in particularly dense woodland, you might want a shorter hammock. Hasn't been a real problem for me yet.
>Also, how important is an under quilt? Can I get away with just a sleeping bag in PA?Underquilts aren't too important, but some kind of bottom insulation is. A sleeping bag by itself will leave you with cold spots on your back unless the outside temp is fairly high (somewhere in the 70s for most people). Lots of people just use a foam pad - you might as well try it once with a foam pad and see if it's fine for you. I have trouble keeping foam pads in the right spot - also they're usually too narrow to cover you shoulders well, unless you hack one up. But several people I know are happy with foam pads and a sleeping bag.
>Here is what I am thinking about right now, I am planning on getting it in olive green with 4ft tree huggers and whoopie slings. 11ft.Sounds like a decent choice. I don't know what the trees are like in PA, but if they're not too big the 4 ft huggers should be fine. If you don't care too much about an extra ounce or two, you might want to get 6 or 7 ft huggers just to be sure.
Whoopie slings work great - easy to use, strong and light. If you're using the marlin spike method to attach them, you might want to consider buying an aluminum arrow shaft and cutting it up to get two pieces for use as toggles. Or just use sticks.