what's better to have assuming the same rate, a mortgage on primary residence or on rental

[Vinson Lee]

Just a random question that I am not sure about but was wondering.  Assuming I had a rental property and a primary residence.  Both have mortgages for the same amount and the same rate and same length remaining.  Would it be more beneficial to pay off one or the other?  What should someone consider when deciding?

This is sort of hypothetical, but I think what I learn from the answer to this may help me understand investing a bit better.