1. Depends on your team, if you get the shot in time the motion shot shoud be better. but when you don't find your oppurtunitys fast, Run and Gun could have the better shot oppurtunitys for you.
2.Motion
3. Both of them use them heavily(Run and Gun is not so heavy on the SF shooting then motion)
Honestyly i recommend to test those strategys with your own rooster from time to time, because they are lot of factors who make one tactic better then the other, so that you see here lots of theorys but in the end it could be different with your team.