The AFG is nice but the PTK is even better. I have on all of my rifles. It gives me much more control.
+1
Along with the thumb stop - have on numerous weapon.
Never tried the PTK, but CP you might just convince me, haha. The gas pedal is expensive but quality. And the pts gaspedals aren't bad either, though I wouldn't recommend on the VZ58 just due to the heat they'd be exposed to (though they can probably take it...). And when you combine the AFG and aluminum gas pedal, you're talking a $100 ergo enhancement... PTS Gaspedal and AFG, you're looking at ~$50-60...
Point being, the thumb rests are pretty great IMO... Giving you much of the benefits of the infamous C grip, but in a fashion in which your thumb is oriented down range at target... Presumably helping with sight alignment and ensure your forearm is less intrusive into your sight picture as your arm/hand ends up slightly lower... Especially with platforms like the VZ58 where there's a low sight/optic alignment... (ARs sights sit much higher...) With the EVO it probably isn't essential since you can c clamp w/ beveled top forend w/o getting into sight picture, but thumb rests on this platform would allow for more consistent ergos across weapon systems if you run a thumb rest setup elsewhere...
Does anyone know if FAB/the PTK has an ATF letter stating that its pistol kosher? I believe the AFG has one stating specifically as much...
Somewhere on the interwebs, I also saw a dude advocating running his AFG backwards making the angle more vertical... Not sure of NFA considerations doing that, but he just preferred that setup on his rifle. But this would probably give you the most vertical grip option without having to NFA your weapon, provided reversing direction doesn't constitute remaking, etc... Who knows with the sig brace decision though...
Found it:
http://youtu.be/oLhJ7dPtpUE