Glad you brought that up, there is a difference. If you are shifting WOT using the clutch, a SoftLoc style clutch actually has pretty harsh initial engagement characteristics due to it's centrifugal component.
I'm one who has used the McLeod Soft Lok. Let's be clear. The centrifugal component is an optional attachment (in the form of centrifugal weight attachments) which comes with the setup for one who judges they need it to control slippage. I've never used it as I didn't need it for my setup. There is no harsh initial engagement with a Soft Lok clutch unless you want it and can figure out with the setup how to get it. The Soft Lok clutch aims to give you quite the opposite and I can say it delivers.
I agree with yellow rose on all this based on my experience. I also understand the OP isn't concerned with the issue at this point in his build and I'm not trying to bust his thread. I just want the facts to be clear and think the OP may want to consider the advantages. I found them to be priceless in my 4-speed racing days which were some time ago. Hopefully more of those days to come soon. : )