Sorry if this doesn't answer your question, but I've never managed to wear through the old shiny brown CAPS despite years of use, whereas I've worn through at least two sets of MG CAPS in a year.
I believe I have a set of old brown CAPS and the matte brown CAPS sitting at home -- I'll see if I can get you some definite relative numbers (not going to break the plastic on those babies, sorry!).
i.Prestige MP XL, stock. Skeered to CAP it.