Mt. Bike shoes FTW, based on your parameters..
"I've read that sometimes SPD cleats give riders uncomfortable hot spots"
I call BS/confirmation bias and all humans aren't exactly the same when it comes to tactile perception. If this were generally true, few would purchase SPD gear. The reason it's not true for most people is because of stiff soles.
What is the magic size of a cleat that would banish hot spots? Think about it: cleat sizes vary, so larger cleats would simply mean some people should experience larger hot spots.
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