I never had any problems with the griplocks moving once taped into position but I always found the trigger bit a real pain. I could never get my hand positioned right and had to splay my fingers around it. I use the AFAW one on all of my rods, they are the ones with the slot cut out of the thread and I've had no bother with them at all. I don't think there is an ideal sliding reel for heavy fishing as they all need a bit tape etc to keep them in place. We don't really buy them to be moveable anyway, it's only so we can fit them over the shrink tube.