They don't use the Linaeum tweeter. The Linaeum is a dipole radiator, and the Gallo tweeter is cylindrical (330 degree dispersion) You couldn't put a Gallo CDT in a box, like you could with the Linaeums.
I've never heard a linaeum, but I do know the Gallo has the sweetest, most articulate highs I've ever heard in a speaker (coming from a former owner of Magnepan 3.6's)