Tiered weapons question

Hello,

Let's say I focus an iron banner engram and want a Wizened Rebuke, I can only get that as a T4 drop. I proceed to upgrade it to T5. Is there any difference between this manually upgraded T5 Wizened Rebuke and one that drops already at T5 from iron banner activity? From what I can tell the only difference is the -1 perk selection choice in each of the two perk columns, but I don't know if there's something else like going on such as slight base stat differences, etc. Cheers