I'm not super-familiar with PRS guitars. I haven't worked on a lot of them since most people don't have the money to own them. haha... However, you are fortunate to own one. I believe they are similar to a Les Paul though. When the factory sets the neck they set it at a 3 degree (or slightly more) angle in orientation to the body... most stop tailpiece guitars are set up this way. This allows the strings to get a better angle on the tailpiece, stiffening the metal to metal contact and giving the guitar more sustain. When they do this, it should allow you to play a set-up that requires a lot less relief. You should be able to set your neck to be almost straight (literally, with maybe only a very-very-very slight relief). First, tune your guitar down a half step... this will relieve some of the string tension for you to tighten the truss rod safely. Then tighten the truss rod until it's pretty straight... then tune your guitar back to what tuning you would like. Fine tune it so make sure it's about straight. Then sight the neck to see how the strings are laying on the neck. If the strings touch the first fret it's obvious that you will need to add a tad of relief no matter what. If it's not, and I suspect that it won't... you might have to adjust the bridge a little. Play around with that, if it buzzes... I suggest setting it back up to how you had it. An alternative would be to get the 10-22/24 frets dressed and shaved just slightly. Since buzzing is cuased by very slight metal contact in vibration, the very little metal that is taken off in the dressing process might allow the proper clearence to run a lower set-up without buzzing. Consult a pro guitar tech if what I suggested isn't satisfactory.