Kickass quilts are a cheap alternative to down, using climasheild green – they are designed to fit Hennessey – but John says on his website that he is confident they will work on other end-gathered hammocks with an easy suspension modification. the website doesnt reflect the true cost, i am quite sure the quilts are reduced to $120, not the $180 as stated. ask John for all details: kickassquilts.com
otherwise, the Jacks R Better Bear Mtn. Bridge hammock has a flat lay design and a pad sleeve. you can use your t-rest, and a couple of ccf "wings" to get you down into the high 20's without any issue of moisture. in the Bridge, using a pad actually makes the hammock seem larger.
*note that in a hammock, an inflatable pad should be 'barely' inflated. a BA aircore or a Exped Downmat pad should be inflated to about 3/4" thick. a t-rest should be opened and allowed to self inflate, and then release air in hammock to get the right "feel". Think of a pad in a hammock like a water balloon.. try sitting on it, and it shoots out from under you. of course, a pad sleeve helps this issue. I dont believe in the case of either style pads that this reduces the R value. It may, but i havent seen evidence is what I mean. CCF pads can come in a wide selection. I have a local Volara (poker table foam) dealer that wants a mere $7 a yard at 60" long for the 3/8 size. If I were to buy 2 yards, id have two 30" wide pads at 72" long. For only $14.
check your local upholstery retailer for anything of this sort..its called 2A Volara.
You may find Hennessey Hammocks and ENO in most retail shops, but those "in the know" dont bother with such large scale mainstream production flops, they choose the Warbonnet Blackbird. Ok, take that last statement with tongue in cheek, but seriously the Warbonnet Blackbird is the shiznit!
(Tom, dont forget, no BB is fully equipped without a Te-Wa underquilt!)
also, you wont have to spend tons of money to get the "hang" of hammocking. this first pic is of my $20 hammock, a $10 foam pad (army surplus) and a homemade tarp (severely undersized..) but hey, i was hanging! this was August of '07 and my first useable set-up. I have gone to ground once since then and that was researched and planned.. (no hammocks allowed in GC-or so it seems) the point is, for under $75 i was hangin'

the second pic is my current setup, the Blackbird single layer, under a spinnaker MacCat tarp. The blue underquilt is made by me, which im also making in small batches for others. a more "professional" approach.

if you can remember, i used to make and sell cat cut tarps to many of the BPL members.. and sleeping under a tarp on the ground is exaclty how i started sleeping under a tarp above the ground.. just an example of backpacking evolution. Funny, we spent the past million years trying to leave the trees and all these chimps trying to get back into them.. lol!