In have run Mcleod and Advance soft locks, and also proshifted and face plated transmissions on the street and on the strip. It IS doable, but there are a lot of drawbacks to using them on the street. My opinion is if your car is only 10% dragstrip, neither is worth the hassle. On the strip, you set the soft lock clutch loose. it slips at launch, and the heat created by the slippage increases the coefficient of friction on the sintered iron disc, thus locking up the clutch. It's an awesome drag race clutch, effective and durable. Running down the street with the loose setting, it will cool off and slip in high gear. So you have to tighten up the spring pressure to the max. Then it is very grabby when you have to slip it maneuvering around a parking lot. Also noisy. And you need to adjust it for wear a lot and adjust it tight for street or loose for strip. There are 6 adjusters on the back of the pressure plate. So you adjust #1 thru a small hole in the bellhousing, then turn the motor 60 degrees, adjust # 2 , and so on. It's a high maintenance piece.
On the faceplate and proshifted transmission, they shift great on the strip. On the street too, but you can not make any slow, relaxed shifts. you have to slam it every time to avoid grinding off the edges of the engagement lugs. High maintenance parts, you take it apart and have the engagement lugs resurfaced every so often. And there is backlash, or slop, between the drive and driven side of the face plate or lugs. When you are trying to go slow, like in the pits or a parking lot, or stop and go traffic, the surging of the engine is not dampend much because of the light flywheel, and so you feel a jerking of the car and a slamming inside the trans as the backlash in the transmission transfers back and forth.
All of this stuff you can live with. But its not worth it unless you really do a lot of drag strip stuff. Good luck, Joel