Played a new Jazz Aerodyne last week and it sounded lovely. I see on the web some have scratchplates and some don't. Are these older models, or are they different in other ways? No sign on fender.com. Does the P aero sound more-or-less identical to the J aero? Just clocked this P/J Reggie Hamilton Jazz. How does that sound (in passive mode) in comparison to the aeros? Also tried a USA Jazz with the S1 switch recently, and with the switch engaged that also sounded sweet. Much different? Any thoughts on the pros and cons of these animals?