All the normal sources I'd use for reliability data don't include the diesel because it isn't sold in the US. Fortunately, I live in the US, so that's not a choice I need to make anyway.
Given the contortions VW is having to make with their latest diesel, I'm inclined to think that if Mazda brings a diesel to the US, we won't be able to assume it'll be as reliable as the diesel they sell elsewhere. At a minimum, the exhaust system will probably be quite a bit more complicated.
