I would run a Synthetic for 10,000 mi or a Conventional/Blend for 5,000 mi OCI.
Right now that would likely be ST Synthetic for $14 for 5 qt at Wally or Shell Rotella Synthetic for $2 a quart if your AAP still has some.
Synthetic at 5,000 mi doesn't gain anything. If it's formulated for longer drains it can cause more aggressive "stripping" on initial fill and actually not do as well. Match the oil to the drain interval you want to run.
This of course assumes you don't have a specialized application.
Disclaimer: The above is simply my opinion after reading various studies (with parts measurements) and looking at analysis on the same engine.