Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

Campag makes a Super Record chainset that works with removable spiders- but only for SRM, at the ~£lots pricepoint, to keep themselves exclusive.

They refuse to supply other PM makers, is my understanding, as they only want to be associated with the best in the market.

Ah, didn't know that. Presumably the cost of making very low-run removable spider chainsets is also pretty monumental, so it wouldn't make sense to sell such expensive cranks with the cheaper PMs.