Let me ask a provocative question - why aftermarket clutches? Typically, the kit manufacturers (at least the good ones) know what they're doing...
I've tried a few clutches on my MBX-6 - I always come back to the stock setup (3 aluminium shoes + 1.0mm springs + stock bell). Others might have better lifespan, but the feeling of the mugen shoes + springs + clutch as a combo is simply unbeatable. I'm sure the Losi/AE/Durango/Serpent/Kyosho clutches are just as good (deliberately leaving xray out of the shortlist due to goofy bearing dimensions that force you to spend more)...
Paul