Mate I suggest that at some ports, they don't give a damn whether your footware has metals in it or not - you take it off and put it through the X-rayer anyway. It wasn't metal in Richard Reid's trainers which led to his present incarceration.
In which case, either
Islander Jock's Blundies
or my RM's
are the way forward.
My Blundies are about to do 4 months on the road between Dakar and Addis...
I shall look forward to updating Prooners about their adventures. The RM's will be shipped.