Hi Kevin,
We have been running a CCM - Meridian (61c) hybrid for a few years now using DMS100 PRI's because we didn't have the Package/License for QSIG. Everything has worked well (Name/number display etc) the one thing that isn't available without QSIG is the ability to route calls in and back out on the same B-Channel for Forwarding etc. I'm sorry, the feature name is not coming to me right now (it may be Tromboning)so you may need more PRI's between the two systems.
Everything else has been great! DSC's route calls over to CCM so there is a nice way to do a phased migration.
Hope this helps!
Rob