Beware that sometimes coding can have nasty consequences. Last year purchased a SFO-FCO from AZ, with stops at JFK. All flights were AZ coded although obviously the SFO-JFK and back were on DL metal.
Well, even though I purchased a Premium Economy ticket and I am a PM, I was not able to upgrade to C+ on the Delta flights until they went under gate control, at which point all C+ seats were obviously gone.
On the other hand, I just netted almost 20k RDM out of a SFO-LHR r/t purchased from VS. If I had purchased from DL the very same flights at the very same price I would not have got 4k RDM out of it.