I have slept in my byer mosquito hammock just about every night for about a year. I have been very happy with it and bring it with me everywhere. I have not had any problems with sagging, and the cords don't get tangled too bad as long as I'm careful packing it up. The only thing to ever go wrong was the attached stuff sack ripped off.
I weigh 180 and my 75 pound shepherd likes to climb in on cold nights. This usually works out well but the other night he tried getting up at 5 a.m. and the hammock tore right in half. I know it's my fault for breaking the weight limit, and would recommend this to anyone looking for a lightweight mosquito hammock.
So now I'm looking for suggestions on my next hammock. I want something similar that can handle me and my dog. Luckily my roommate has a byer that he's letting me borrow until I decide.