| Sintered ones are fitted at factory, they are better and last longer (ish) but more expensive. (even with your DSC discount)
I've known guys on R's and SPS's who use the standard ones without problems when the sintered ones are worn, depends how many race starts you want them to last!!!!
I've never know a new standard clutch to slip (except when the springs are worn)
Common sense really, and budget. A new standard clutch is better than a worn sintered one. | 
wilf
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