I really enjoy both of my SC594's. After always feeling other guitars required an adjustment period, the first time I held a SC594 it just felt right. If you get a chance you should grab one (or more!).
I have an SC-58. That is close to the 594 single cut. It is a good guitar. My 594 is a double cut. I have times when I gravitate to the single cut guitars but am usually on a double cut. When I was looking at the 594 guitars I had seen a video where they compared the single cut and double cut versions. They sounded the same and the person in the video said that same thing. That made me go with the double cut since that is where I typically go first.
I recently got a core SC594. I love it! I've had several PRS SC models (Tremonti, SC250, SC245, etc.) and the 594 is definitely my favorite. I still have a Tremonti too but the 594 just feels right for me!
I’ve owned core and s2. I can honestly say I prefer the s2 BUT you cannot go wrong with the core. I personally didn’t love the TCI pickups in the single cut. I wanted something with more hair. When I modded the pickup it felt much better. But I can do the same in the s2 and save thousands. Both feel the same to me in terms of playability and resonance. Which makes sense when it’s the same bridge, tuners, and wood types, although the core has higher grade maple top and different neck construction.