$4 harbor freight tie-down straps are good for suspension... I'd hate to see you on youtube when your buddies on the river catch you falling down . . .
Hopefully those straps will hold . . . I didn't see how they're used, the buckles should not be trusted... the forces on each strap will can exceed the weight of the occupants. . .
Nice looking rig!
"Do or do not, there is no try." -- Yoda