Bòtannan ùra new boots

I suspect there is a design flaw with these boots - Cotswold Outdoor have replaced them twice for me - no questions asked. I am reluctant to try a different brand when these, despite their propensity to tear, are so comfortable, even on twenty milers - no rubbing, no blisters. 
They will have their inaugural outing tomorrow when I am planning another chunk of the West Highland Way - weather permitting.