from their web site:

• Unlike nylon, which stretches 35%- 40%, "Custom Rope" only stretches 12%. With
  only a 12% stretch, it does not have the dangerous recoil that nylon ropes have!
  
• You must have a certain amount of stretch, which is Kinetic Energy, but you don't
  need so much that it is dangerous.

.......
"CUSTOM ROPE" is custom made!

• It can be ordered with loops, hooks, rings, or screw pin clevises.
  
• It can be ordered with full or partial nylon covering.
  
• It can be ordered in any length.

so however you need it made to work for your application.

 

Yeah, if it's on their web site it must be true.

Open hooks aren't safe for most recovery.
I'll use an open hook strap/rope for towing a car off the road, but off-road, never.

The amount of stretch is dependent on if you're doing a static (steady pull) recovery or dynamic recovery. The high strectch of nylon, for dynamic recovery, adds force to the recover without shock loading the vehicle as much as little to no stretch would.