28.5 is not a size 10 lmao, ofcourse boot size depends on your foot and everything else but for example, i wear a size 11.5 shoe and im in a 27 boot, i fit real snug in a 26.5 which i considered buying but i went with the more relaxed fit because i dont need them to be amazing performers, however mondo points (boot sizes) dont convert directly to a shoe size, i would recomend NEVER buying a boot unless you've tried on that model in that size.