As far as I can tell, the curved top tubes were 93 and earlier. I'm sure there's overlap. I know with most GT, Robinson, and Powerlite, the Completes were pro's. The Pro Team models were the XL's. GT had the Pro series Team. Robinson had the Amtrac. Powerlite had the P-61. I think Auburn had the CR-20RX.
Then there's the whole Steel, Cro-moly and Aluminum subframes they had. This changes nomenclature too. Of course this is just what I can vaguely remember from a decade and a half ago.