Thanks RW,
Speculation: Rotax probably had a far easier time of entering the World market than entering the USA market. I am sure there were several/many factors for this, not the least the availability of LyCon's (& derivatives) in the US, compared with other markets AND the conservatism of the flying world.
Despite Rotax 9's, now well proven, record for reliability/excellence, we (Australia) still have LAIM's and pilots, who consider the Rotax 9's to be overly complicated/difficult engines to maintain/work on, "turn their nose up" at the very suggestion of using one.