For the sake of conversation let's say you wanted to go Private Stock to get this; if nobody has done it you would REALLY have to want this configuration change as the upcharge is pretty hefty. Trust me...I wanted to do a full hollow-body SC 594 but the cost was prohibitive.
To me its not the 2 extra frets on a " 24 " its the even easier access to anything above the 12th, and I think the neck pickup on a 24 fret can be more useable in some cases
If you have played or owned a Santana for me anything to give you a bit more space up high would be welcome, for me 594 Santana would be killer IMHO it would be even better at 25" Scale for me !!!