Been told, don't know if it's 100% true, But been told to only run alum. shoe with a clutch bell that has only run alum. shoes
as in
if you change from comp. to alum. with the same bell the alum. shoes will wear quicker than normal and slip more than normal causin gextra heat

I had done this a while back and the alum. shoes wore out in a matter of maybe 10 tanks of fuel in addition to that I had about 3 clutch springs break. It was making me nuts.

running comp. now next time I try alum, it will be with a brand new bell