Yes the regular McCarty is still being made and is one, if not my favorite PRS model. Don't get me wrong, I love my 594, but the neck on the regular McCarty, the Pattern neck profile, is just one of the most comfortable necks I've ever played. Interestingly, another neck carve that I really enjoy and is among my favorites is the one on my Les Paul 1959 reissue. When I measured it with a caliper, it turned out to be ridiculously close in thickness to the Pattern neck on my McCarty (R9: 0.8625" @ 1st Fret & 0.981" @ 12th; vs McCarty: 0.8755" @ 1st Fret & 0.9465" @12th).
I actually very marginally prefer the sound and control layout of the 594, but the neck carve of the regular McCarty, as I've mentioned before, is very marginally more comfortable for me. As a result, I feel my technique is ever so slightly cleaner and I play just a little bit better with the regular McCarty. With that said, I've had the McCarty a bit longer than my Double Cut 594, so it might be an issue of familiarity. Something I prefer on my 594 is the satin neck finish (maple neck). That thing is ridiculously smooth. The body on the 594 is also slightly thicker, but I didn't notice any comfort loss with it. I'm also pretty happy with the scale length on both guitars. I can go back and fourth with very little to not adjustment time.