Well, the shoes (Keen Commuters) just arrived today and they fit me nicely, though they feel like clod-hoppers to walk around in (at least there is not much heel to toe drop). Tomorrow I will try them out on my grocery run and on a group ride in the evening. It does look like I will need to adjust saddle height a little bit because of the extra thickness compared to my sneakers, which could become a bit annoying if I then want to hop on in regular shoes for a quick errand (no quick release on the seat post). It will be interesting to see how much difference the shoes make, before adding any foot retention (I still may do that later).