My .04 worth...

If you are kicking in doors for a living and may need to retain your weapon or you have a bunch of crap bolted on the handguards, then VFGs are good.

For close up shooting or even longer distance (<150 yards) shooting standing, no VFG is the best/fastest to use.

Two reasons why.

Skeet and Sporting Clays Shooters. Lots of gun movement and not a lot of recoil. They dont use them.

3-Gun shooters. Lots and lots of QCB type shooting and a little bit of longer range stuff from 200-400 yards. Almost nobody uses them.

And perhaps the main reason why I dont use or own them, they scream Mall Ninja.