I'm on a stock replacement Sach's clutch and it doesn't slip, much. Roll on throttle and it's just fine. I can launch most of the time and it grabs. The only time I've had it slip is if I really get traction or launching in 2nd.
So I'd say there's no reason to get anything but stock for anything N/A.
Don't "think outside the box".
There is no box.
Do it correct, or do it twice.