I have had several pairs of these particular Clark's in the past and they are so comfortable.  The only problem is that Clark's no longer makes this particular sole.  Their shoes now have a higher heel and if you do find a mostly flat sole it isn't this one and it isn't as comfortable.  It took me weeks to find this pair and I'm disappointed that it will probably be the last pair like this that I'll be able to find.  This is a shoe you can put on first thing in the morning and won't need to take them off until you are ready to go to bed.