I originally bought the Siren Sport GRX but found after walking in them for a few kms that the eyelet stitching was rubbing my toes and were impossible to continue with. I was faced with the prospect of an expensive pair of useless shoes, albeit nice looking ones. Because of my disappointment, I did what I would not normally do, and contacted Merrell in Australia. They kindly invited me to send them back, even though I had bought them from an outdoor store in Perth - and by reply paid postage. They then suggested the Moab waterproof shoe, and in a size larger, which I received last week. I have not tested them in water yet, or done too many kilometers but they are wider across the toes and wonderfully comfortable from the few short walks I have done.I took one star off as they do not have the good looks of the Siren Sport, being a dark grey, and quite chunky looking. I am looking forward however to wearing them on a long hiking trip in a few months time. Five stars to the Merrell people for their great customer service.