Wow, had a very interesting surprise at the range today. Put a Ghost 3.5 connector in my 17. Seller also suggested a 3 spring kit to actually get the trigger pull closer to the 3.5#'s. With the 3.5 connector installed, I also put in a 6# trigger spring, an RP Plunger and finally a 4lb Striker spring. Trigger felt great, so went to the range. Each time I pulled the trigger the gun shot TWICE. Had a more knowledgeable Gent from the Gun Counter come check it out. Same thing. Skipping to the conclusion. The culprit was the 4 lb striker spring. Dont go that light. Switched the std spring with the 4 # spring 3 times trying to get a different result. Its the 4# spring. Easy to test your gun if you add this kit. Dry fire the glock, with the trigger still pulled, pull the slide and slowly release the trigger to see where it resets. If it does what it should, it resets, or in this case it fires. Not good. Has anyone encountered this?