I live in trainers. I have learned that my size and model is New Balance model 624 in a 4E wide and a size 42 European. I use the European sizing by preference because it gives a finer sizing than the British or American sizing.
It's almost frightening that I can walk into the shoe store and walk out again in less than two minutes with my shoes.
But if I want to buy any other shoes, I have great difficulty. Invariably, the shoes on sale are not wide enough. Sometimes I have bought shoes in a larger size like a 43 or even a 44 to get enough width. But almost invariably again, they are just NQR. And forget about elastic-sided shoes. They are just so tight that I can't even get my foot into the ones with the correct length. I would love a pair of espadrilles. Yeah, right. Dream on.
As I said above, I live in trainers. They're the only ones that 'fit right'.