I wear size 10-11 street shoe, but in cycling shoes I wear 43-44. I purchased these shoes in 43, but I wish I had ordered a 42.5. I have a skinny heal and a wide forefoot, overall my foot is boney. The Fizik R3 fits my wide forefoot and accommodates my narrow heal. The heal counter rises high onto my achilles, it bothers one of my feet but not the other. My foot feels secure in the shoe, I credit the arch support for that. I have one normal arch and one flat arch, but I like footbeds so my feet have something to rest on as I stand on my pedals. These shoes have the arch that works for me, it isn't noticeable while I am riding but i can feel the arch pressure when I'm walking around (although it isn't painful, just pressure).
These shoes are really comfortable. I like long rides, with my previous shoes I would get sore feet, but with these shoes my feet feel great. I just returned from a weeklong bike ride that covered 550 miles and 22,000 vertical feet of climbing. I never experienced any foot discomfort during the ride.
I have the Fizik R3 in red, they look awesome and the color makes it easier for people to seek me out.
I would definitely buy this shoe again!!