Will polypropylene work for full suspension?

[John Smith]

The suspension point I would use is only like a foot or a foot and a half from the top of my head. I just hope the rope won't stretch too much to the point where I fail because of it. I also weigh 240 pounds so I worry I will fail because of having a bigger neck as well.

 

[iDieUDie80]

I also have this question

 

[Aap]

Why not just hang from it/pull on it using your hands and see.