Thermoform upper/Full length carbon midsole/Anti-bacterial thermoform insole/Offset straps/40-48 (42-46 in wide fit)/Weight: 804g/pair
Contact: ultimatepursuits.co.uk

In the M-300, Shimano has
produced a truly custom fit shoe at a third of the cost of previously available ‘tailored’ footwear. Three pieces of thermoformable plastic: a wraparound heel cup, a triangular section over the bridge and a long narrow section parallel to the sole. Running from buckle to toe box, this is responsible for a vital element of the M300’s fit as the outside edge of the human foot has the highest number of anatomical variables.
A heat-mouldable footbed is included with anti-bacterial, optional arch supports and metatarsal button. Shimano uses a full-length carbon midsole for stiffness. Bonded to this is a dual-compound rubber outsole, moulded in one piece to prevent the lower durometer section delaminating.
M-300s are only available from a selected band of shops due to the fitting process. First, the shoe (without footbed) is heated to 120°, the footbed and foot inserted and then the shoe tightened as normal. Both foot and shoe are placed in a plastic bag and attached to a vacuum pump. Sucking air from the bag conforms the shoe to the foot. Once cooled, the footbed is removed (optional arch supports are stuck on at this stage), heated and then placed in the shoe. With the shoe tightened again, the rider’s weight — while standing — shapes the footbed.
Combined with the high spec, this custom fit results in an unparalleled level of comfort and performance. Gone are the days of ratcheting a shoe super-tight to prevent any foot movement. Grip across the width of the ball of the foot stops sliding and prevents any constriction: toes are free to wiggle. The heel cup moulds around the Achilles tendon and one-way knap lining prevents the foot pulling backwards, within the shoe.
While manufactured in half sizes, Madison — the importers — are not stocking them (or the smallest sizes 36-39). We feel this is odd as the shoe is all about getting the ultimate fit. Thankfully, Madison will be carrying the wide fit M300-Es. Despite this minor quibble, for the tester (who takes size 42.5) a 43 — shrunk to fit — has resulted in quite simply the best fitting and performing race shoe he’s ever used.

MBR RATING: 10/10