DoctorBwrote a review of Shimano Dura-Ace PD-R9100 SPD SL Pedals on July 21, 2019
Familiarity: I've put it through the wringer
Great pedals. Unfortunately they will start clicking after about a year and need to be taken apart and serviced. It's been a fairly well documented problem with the 9100 pedals; feel free to look it up. Dunno if they just lube them improperly or what, but there are tons of videos on the web documenting the problem and how to service them. I've gone back to using older ultegra pedals which have yet to produce a clicking sound, time will tell.
Otherwise solid pedals. Very light. Just wish the bearings where more reliable. Had over 7000 miles on them when it started clicking, so it's not like they have this problem out of the box, but it seems like a fairly common problem that will eventually manifest. Luckily they are not that difficult to service.