Update: I spent some time today checking out every model recommended here that I could get my hands on. This included: the SSH, DGT, 594, Custom 24, 24-08 and 408. Unfortunately there wasn't a 509 or 513. All were wonderful out of the box; a real testament to PRS design and build quality. Any of them would be nice additions but I did have some favorites. Below are my thoughts:
Custom 24:
The quintessential PRS guitar. Has a lot going for it and I understand why so many recommended it. However, there is too much overlap with my Suhr Moderns.
Custom 24-08:
Love the switching system and resulting tonal flexibility. Same comment as above though.
408:
Sweet guitar. Love the switching system. Really versatile. May buy one one day. However, it lacked the Les Paul type tones I am wishing for from the neck.
DGT:
Another great guitar, as they all are. Like the neck pickup but didn't love the bridge. Good vintage tones but a little too harsh for metal, consistent with what was mentioned here. The neck, while nice, was my least favorite of the bunch due to the slightly narrower width.
594
Tied for first place. Great Les Paul style tones. Worked well for metal. Nice neck. My favorite visual look. Only real downside was that it wasn't as tonally flexible as the other guitar it's tied with, as split sounds were usable but not great.
Special Semi Hollow
Tied for first but may actually have the edge. The most flexible and best feeling guitar I played today. Could get into the Les Paul territory I want, great switching system, nice single coil sounds, no volume loss, light weight. Only unknown is its ability with metal and other high gain as I didn't get a chance to put it through its paces there.
That said, I'm now debating between the 594 and SSH. The last bit of information that I need is really the SSH's ability to handle metal and high gain. To those of you with one, can you elaborate on how it handles those sounds? Also, any experience with how it handles something like Van Halen?
Thanks all for your help!