I think another investigation is unnecessary, a waste of time and resources, regardless of who leads it. Unnecessary not in the sense that nothing else will be brought to light over the Benghazi incident, but because nothing will be done about whatever is found out.
It is all just political grandstanding, and we have far too much of that.
Republicans want to use the anticipated outcome as yet another club to beat HRH Hillary Clinton. They just need to get used to the notion that, if she ultimately decides to run for President, she will be elected. The Republicans have no one to run against her that has a chance of winning.