I'd trade him into the fish store or sump him. See below if you are thinking about a pistol shrimp / goby combo...fyi they are my favorite and the reason I got into the hobby.
Assuming you want to keep things on your sand bed the only pistol shrimp I'd trust are the Alpheus randalli (candy cane / red stripped). They stay nice and small and don't really tear things up, at least not from my experience.
They get to around 2" and you usually pair them with something like a yasha or red banded goby that max out around 2.5".
If you don't plan on keeping things on the sand bed and your rock is nice and stable, then the other one I trust is the Alpheus bellulus (tiger pistol shrimp). The get a lot bigger and definitely can move some dirt around, you really can't keep anything on your sand bed with one of these guys. They get around 3" in size and you usually pair them with something like Amblyeleotris randalli (orange stripped prawn goby) which can get to 4".
So after that is all said and done, the Tiger pistol shrimp is my favorite...(I currently have a red stripped/ rays combo) The smaller species just seems more skittish, I rarely get to sit and watch them working...
The tiger, I would get to sit and watch for long periods of time...it was always out and about. I don't know if that was because of his partner fish was braver or it didn't care because it was big. I guess every tank's luck will be different...no 2 fish/shrimp are the same.