Er....your friends handicap is 30?!? Maybe he should slow his swing speed down a bit, as i think he may still slice the ball regardless of what shaft we recommend, or get some lessons, but......maybe try a heavier shaft for more control, like something in the 80g range that's tip medium/soft to help the slice. Or maybe try a shorter shaft, say 44 1/2" that will give him more control.
A Diamana ilima in 'X' flex springs to mind. Good luck :)