I am a recent convert to ultralight and am still tweaking my system. I am using the ULA Conduit for a pack and after contemplating alternatives decided to go with ULA's recommendation to use the ThermaRest ProLite 3 mattress for the frame.
My only concern is keeping the mattress dry during extremely heavy rains. I will be using an internal liner for packed equipment because I find pack covers don't work, but due to the "universal pad holders" in the Conduit, the ProLite will be inside the pack but not protected from wetness by the liner.
Since I often use down, and hike in the Northeast, if my sleeping pad gets soaked it could cause a problem.
One idea I came up with is to put the Prolite in its own liner. However, that might make it difficult to partially inflate after all the other gear is packed.
Another idea is to let it get wet and carry a piece of light plastic to cover it with at night and thus protect the sleeping bag from the moisture.
At some point I might move to a poncho/tarp which will solve my problem, but I'm not quite ready for that yet.
Short of switching to closed cell foam, any thoughts on my ideas or other suggestions that might help?
