Limited experience with either item in camping, extensive experience with both on my bed. The fleece is heavier, relatively bulky when folded, rolled or stuffed, and stays where you put it. The liner is lighter, less bulky, and slicker than snot. One can spend an active night chasing the liner around the bed and onto the floor. Dogs love the liner as a snooze locus, but slide off the bed in hilarious fashion when they jump on it. (I don't get out much). Dirt, debris, and dog hair slide off the liner, and are attracted by powerful molecular forces to the fleece. Neither seems particularly warm when wet (don't ask), but both can be squose squosen wrung out easily and dry quickly. The army apparently designed the poncho-liner system for use in mild wet climates, and I thing it is marginally better. Laced into its poncho, it would be less elusive. And as indicated above, the least expensive, mildest-weather-rated rectangular polyester/nylon bad might be just as effective. No experience with fire issues, but suspect these, like most synthetics, would be quite flammable.