I just bought my first pair of Roper Horseshoes after my husband (also an
endurance rider) gave rave reviews. They seem comfortable enough, and they
are entirely leather, so maybe they'll hold up better than the Steel Riders.
If they don't work, back to Miller's.
I find that riding sport shoes are comfortable enough to get down and
walk/run for a ways as long as they have an adequate achilles tendon notch.
I like the added ankle support that the higher cuffs give over a standard
Nike, etc. running shoe.
Good luck finding what works for you.