Hey Brian K Berry , typically when the config is set for traffic to be (re-)marked on ingress (say at a LAN GW or something), and the route is to a peer, naturally the traffic is going egress SVR with the prescribed markings. So if the network/neighborhood you are peering across can be trusted to carry those markings all the way through, you should be good to go.
That said, I've definitely run into cases where the network did NOT preserve my markings (it was over public broadband). In that case, I had to set my waypoints in that neighborhood to re-write DSCP values as well. That had the overall effect of ensuring the traffic was consistently marked when it left my data-center router, even if my markings got messed up in flight from when they were first marked at my branch. The nice part about the service and it's service-policy being global, is that even if both routers are re-marking, they'll always set it the same.