It's comfortable (for most people), it raises your legs, it is restful, it lets you catch more breeze (important for hot areas), it allows you to get more rest during rest stops, it's easy to use, etc.
My hammock sets up in 1 minute, and I expect to use it all the time for rest stops and sleeping. Whereas other hikers will be resting by sitting down in the shade and swatting mosquitos, I'll be completely lying down with my net pulled over my hammock, catching the breeze. This will even make it possible to sleep in the hottest hours of the day and spend more time hiking in the early morning and late evening to avoid the heat. To be fair, I haven't tried this schedule before and don't know how it'll work.
Why a tube net?
Some hammocks come with netting attached, which seems like it would be more convenient. However, mosquitos can often get to you through the bottom fabric of the hammock. I could make my own hammock with an impermeable fabric such as silnylon or cuben, but then I would lose breathability and the ability to catch breezes, which I suspect will be very important on the PCT. Bug netting significantly slows breezes but does not stop the flow of air. Finally, a tube net can be used for ground sleeping as well, whereas you'd need a separate net for the ground if you had, say, a Hennessy hammock with an integrated net.
Why pads instead of an underquilt?
I use pads (see previous post) because they provide the same amount of bottom insulation as underquilts (but less ease of use) for less weight, and because they can just as readily be used on the ground.
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