im thinking of making a sand team after talking to Pokemon-Ultimation 
and excadrill as we know is a great sand team member but im unsure about the trait 
sand force - +33% onto rock ground and steel moves in sand storm
sand rush - doubles speed in sandstorm 
why have sand force - makes moves more powerfull (in s storm)
why have sand rush - doubles speed which meens i dont need to bother adding speed evs or speed nature can use evs on stuff like def (in sandstorm) 
at the moment i have excadrill  adamant  sand rush  252atk 152def and 100speed @life orb
what is the better sand force or sand rush 
which is most comonly used