If they are as bad as the B&M kit was on my FRST they are deffo shit mine lasted about a week before I was fed up of missing gears and crunching the box to death that I ripped it out and put a standard one back in

My understanding also is that the prehistoric mt75 can only change so fast anyway so you quicked the gear change anymore you smash the synco's.

Best of leaving it standard and replaces the bushes to make them feel tighter