There is no such thing as a universal size guide. There is no such thing as always being a UK10 (unless you don't care how your shoes fit and you only care
Buying International Products Online
EDIT - MARCH 15TH, 2016: THE US JUST PASSED A LAW INCREASING THE LEVEL OF EXEMPTION ON PRIVATELY IMPORTED GOODS, FROM $200 TO $800 SO NOW PROVIDING THAT YOUR