Had not heard of Haven before. I have had Hennessey Hammock(s) for a long time and like them. Like Haven, it is designed to lay flat...more or less. Getting diagonal is the way the Hennessey achieves this and it packs very small. My biggest problem is that it is so comfortable I have a hard time falling to sleep if you can believe that. Getting inside with a mummy bag and a mattress is a little problematic and hope you don't have to get up and pee much during the night. It just takes a day or two to get used to it. Then, I have a hard time getting up in the morning it's so comfortable Now, I pack it as a backup to my RTT or if I ever decide to backpack in somewhere. To me, anything beats sleeping on the ground. I can do it if there is a good mattress underneath, but a hammock is so comfortable. I have slept through several huge thunderstorms in it and was mostly dry except when high winds blew a little rain under the fly. Storms so bad I started wondering what would happen if lightening struck the tree I was using!