I have a PRS SC245 with Abraxas bridge and The Mule neck, and it's my best sounding guitar. I have a custom 22 too, with 57/08 pickups, and tonally they are quite similar guitars, being the custom 22 a bit thinner and stratier, but the greatest difference between the two lies in the pickups.
The PRS are great pickups, but IMO the Abraxas sounds fuller, a bit tighter in the bass response and with a very nice upper mids that makes the guitar cut better in the mix, in contrast with the 57/08 that sounds a bit scooped in that frequencies.
So far the Abraxas is my favourite BKP bridge, and supposedly the neck is a hotter Mule, my favourite neck. My guess is that you're gonna be happy with the result.