I purchased the MBT Tunisha as well as the MBT Kaya (both mary jane styles) and I can definitely say that the Tunisha falls short.  It does not feel like it has the same rocker action as the Kaya.  In addition, the sole did not feel as cushioned.  When wearing the Tunishas, my heels kept slipping up and down as I walked.  I can imagine that I would develop blisters with that constant friction.  I also suspect that the buckle might not keep the shoes in place as well as velcro or laces.  I tried two different sizes in the Tunishas and they both had the same problem with the heel slipping.  I didn't experience this at all with the Kaya.  The Tunisha style is cute and certainly appropriate for work situations, but I didn't feel that the physiological advantage of wearing MBTs was noticeable with the Tunisha.  Try the Kaya instead.