UPDATE: Reviews section refreshed, redesigned, searchable: Go take a look
Well.?
20mm is stiffer, and 5mm
Not sure about the new RS 15mm Maxle Lite but surprisingly Fox's QR15 is heavier than Rockshox 20mm maxle lite despite being an XC standard (*)
15mm should allow for either smaller lighter hubs, or bigger longer lasting bearings in the same size shell. In practice it tends to mean the same shells and bearings with a big adaptor which ends up being less good, but not always.
Oh and yes 15mm is less stiff though both are effective... But there's a reason Fox use 20mm for 36s.
(* despite all the toss MBR keep spouting... They repeated the propaganda in an article that actually included the correct weights, that was good)
20mm is a perfectly good standard, that's been around since the year oat-cake.
15mm is in all practical aspects exactly the same as 20mm, but of course incompatible.
and it cost $XXX,XXX to design, establish and advertise, and we're paying for it.
clearly a sign that bike design has peaked.
