The M32 gearbox gets a bad rap for being unreliable, but it's only unreliable with overtuned engines. It can only handle a certain amount of power/torque and anything over those limits will blast it to shreds. If it wasn't reliable on a stock engine, manufacturers wouldn't use it.
And yes, I'm fairly sure the MA version was sold in this country, they certainly used it in the Giulietta which is basically the same car.