I honestly have no opinion or basis for judgment on that one - better ask your wife!
I've been contemplating the spreader bar solution too. Seems like it might be easier, but then again you're right about the quickness and weight savings with a single suspension. I'm sure the "normal" rated suspension is fine with the addition of your son, but do you have any thoughts on how to strengthen the supports enough for a second adult?
Wow...that would be HUGE
As a side note, I'm a few days away from prototyping my double-hammock tarp idea.
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