Re: Full lenght guide rod, pros/cons?
Different animal. The guide rod in question was designed to prevent spring bind. There isn't enough room inside a dust cover for the recoil spring to bind so the "fix" is to a non existent problem. The FL guide rod comes in quite a few configurations. One piece, two piece, tungsten...to add weight and even a mercury filled guide rod to reduce felt recoil. Do they work ? For me, no. But shooters still buy them, mostly for the "cool factor".
The difference for the Group Gripper is that it does work if you can't perform the the fitting. It's simple to install and less expensive than having a pistolsmith do the fitting necessary for tack driving accuracy. Don't expect the same result but as LD stated, a 30% improvement is about average.