just bought a pair of rm williams craftsmen in black. Size 9f w leather sole.   I wear a orthotic insole with it and it fits really well with a thick sock.   Size 8 with and without the orthotic just did not work.   My only problem is i am getting a little bit of heel slip in the left boot. Right boot is a much more snug fit and my foot does not move much.    Clearly my feet are not identical. Should i worry about this?