Toyota Altezza in us?

just getting in to cars as ill be buying one soon (last one my customers had my customers parents bought my customers and my customers was wondering about the toyota altezza Vag com 16.8, as my customers understand it came to the us under the name of the lexus IS and my customers was wondering since there were two versions of the altezza what is the second version and is the IS the higher or lower class model and also just tell my customers if my customers is wrong about this whole thing