I guess I just remember getting beat up about those kind of connectors when we could still use SO cord under computer room floors. They wanted some kind of cord grip with a rubber insert and a locking ring like the RS devices use.
Of course when they said everything had to be FMC they just used the regular clamp connectors that immediately pulled out and you were looking at unprotected THHN.
Those were designed for a raceway that gets strapped within 12" of the box according to a rep I talked to about it.
