Lower efficiency of smaller sprockets is well known, regardless of material (if only due to increased vibration from chordal action). As you say, wear rate depends on material and design - but to say that these sprockets won't wear any faster is to pre-suppose that the same material and designs can't be applied to larger sprockets and chainrings. All things being equal, smaller sprockets and chainrings do wear faster.graeme_f_k wrote: ↑Sat Jun 03, 2023 11:51 amLower efficiency and faster wear pre-supposes no change in materials or design. We've been here a zillion times before, I am old and grey enough to remember the nay-sayers on Ultra 7 vs Standard width 7s blocks and chains. And, for that matter, 12T vs 13t, then 11T vs 12T ...
However, I am absolutely certain that at least the chain will wear faster with these smaller sprocket and chainrings, since the same chain can be used with the originally sized 12spd sprockets and chainrings.
One might be able to argue that any drop in efficiency or increase in wear is insignificant. But to argue that they don't exist is ingenuous.