NOTE: Question Answered, Shoes Ordered. Thanks @
ThermionicScott
I live nowhere near a store with a reasonable inventory of bike shoes to try; so I generally must order online. I did, however, get the opportunity to try on a pair of Pearl Izumi 47s at a retailer in a city I was visiting. This was after about 20 miles ride and some walking, so my feet were partially expanded, though not what I'd experience on a long ride.
The 47s fit exactly -- that is, my feet fit in the shoe without painful pressure -- but there was no room left over at all. In an ideal world, a 47.5 would be perfect, giving the option of wearing heavier cold weather socks or allowing room for swelling at the end of a century. In the real world, I can get either EU 47 or EU 48 in the particular model I want.
Given the choice noted, what would the experienced among you recommend?
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Note: the model in question is the "All Road" for use on errands, sightseeing rides, etc. I ride road but need some walkables to use on the days when I'm not going from car/home to bike and back. The "All Road"s together with SPD cleats and pedals are affordable enough to justify their coexistance with Look or SPD-SL road shoes.