I've had some time to compare the Special to the Old Smoothie. The Special has a much more flexible tone pallet due to the 3 band EQ. The neodymium pickup is much more mid present compared with the more mid scoop of the OS alnico pickup, probably accentuated by the off string pole positions.
The OS has a certain "zing" that is also present in my 1980 SR but if I was using flats I don't think it would be there. Both the Special and OS appear to have the factory roundwounds so should be very similar in that respect.
I don't play with flats, other than TIs on my CS Pino, but I don't think the OS would give you anything with flats that the Special couldn't. The lower weight combined with all the other improvements over previous SR generations make it the best player's choice in my opinion.
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