I dont know if its WAI, but i happened to notice that madstone rage (the +2 strengh +4 con part) is not stacking with SWD (prestige enhancement), this make the boots look pretty bad to me,

you still have the armor, but it doesnt stack with barskin,
you still have the BAB, but it is the same as divine power clicky

you still loose your capacity to use spell, clicky and wand which can be really troublesome sometimes
you cant use it at the same time as Combat Expertise, which is pretty much a must have for any tank (and so SWD)

when i sum all that, i see that even with 2 madstone buff (which cant be all the time) it only give me +4 CON (since SWD give +4 ST +4 CON)

so either, i keep my boot and go kensai, either i bank my boots, i dont like either of those solutions

any thing that i am missing ?