GE Rx3i and OPC Server

We currently have done a few small projects using GE's RX3i and iFix SCADA using GE's Proficy Driver.
In the Rx3i PLC we need to publish any tags that are required in the SCADA as "External" so that they are accessible by Proficy Driver.
I was wondering what would be the downside to just publishing everything as External and then letting the Proficy Server (or any OPC server) just pick the tags that it needs as opposed to ONLY publishing a limited number of tags.

You will not notice any difference in either the PAC or the SCADA. Only those used take up band width, it may take a bit longer to validate to download the first time you do it. The PAC processor is fast enough to not notice the difference in all but the very largest of projects even then I doubt that it would make much of an impact.
Try it and let us know if you see any differences.

Thanks Russ, Current project is well underway will try on next one. Or if we have any mods required on this one and I can "slip" it in