as mentioned before the Moroso screws seem to be a little meatier than a standard screw of the same claimed size,I know when I changed screws after several slick changes the holes were getting sloppy but not stripped out, bought the Moroso's and all was tight again,, one other thing you might look into would be try to find a metric screw that is slightly larger in diameter than the 1/4 screw,, as far as balance, I personally think it would be neglegable but if you know someone that has a bubble balancer you could check it before and after if for nothing more than piece of mind.

Light travels faster than the speed of sound,,,this is why some people seem bright untill you hear them speak.