I recently picked up a set of these wheels (http://mercurycycling.com/collections/m5/products/m5c) due to an awesome sale ActiveGearUp was offering. At any rate, these are my first set of carbon wheels (I have always rented race wheels in the past) and I’m not sure what tire width to run given the tech specs of these wheels.
I’m somewhat familiar with Crr and how wider tires also offer added comfort, but I’m most concerned with what the proper tire width is relative to the performance of the entire wheelset / bike system (not solely Crr that could be eliminated via more drag).
I am not an expert but I would give these a shot I believe they would match up nicely with the width of the rim and give you a little bit of comfort as well. the 24mm.
I’d use a 20mm Supersonic on those. Tire narrower than the brake tracks is more aero. The rim is listed as 23.5mm wide, and looks like it has a pretty wide inner width, so 23mm tires will stick out. Definitely wouldn’t put 25s on for a race.