Look Keo Classic 3 Pedals – vs – Shimano R540 Pedals

At 280 grams The Keo Classic 3’s are 50g ligher by using a composite material. Is there any reason to go with the R540’s? One reason is price, with the R540’s selling for between 15-20% less than the Keo’s. Each use their own cleat system but with the holes in the same place meaning road shoes that are SPD-SL compatible are also Look Keo cleat compatible.