Well 42 would probably stretch out if they fit a little tight but 1/2 size can make a shoe fit perfectly. why not ask for measurements? And I'd go 42.
Kind of related to that. Is it to demanding to ask for insole and/or outsole measurement when buying something on bst or ebay? Some responses I've gotten amaze me.
"It fits like x brand size x' Well this assumes I have that brand which is a totally different aesthetic and shoe type.
'Fits like stock/usual x size' Not...