I am considering CBR 7 video with AC3 audio at 192, subtitles and CC.
Is this a safe data rate for playback off a replicated DVD on set top as well as computers?
We have 500 mhz Imac and it seems fine.
Seems to me like it should be fine. It's well under the specified limit.
Generally a replicated disc will play back more reliably and with fewer problems than a burned disc, so if your test burns are playing fine expect the replicated discs to be more fine.