Hi Mike
AWM uses 12 bit sound samples, AWM2 (2nd Generation) uses 16 bit sound samples.
Main problem with Yamaha Arrangers is the output sound system which gives the voices a compressed CD like sound.
When Tyros 2 was launched its SA voices were way in advance of the Motif line, and the Articulation voices on the new Motif are a variation on the Tyros 2 SA voices.
As to Roland, have a listen to the new Atelier Organ range as they have a vastly improved sound engine which will most likely be used in Roland’s new Arrangers. (The sound engine in the existing Atelier Organs is pretty much the same as in Roland’s existing Arrangers.
As to Tyros 2 being cutting edge when it was released, then No, but it did add new sounds and features that allowed it to stay up the top with other manufactures Arrangers.
Hope this helps

Bill