In theory, the I beam shape is better for rod loads. (Really) high end rods are usually I beam. That said, manufacturing details & heat treat are at least as important as basic shape.

I think for the OP's application, a well made set of either would be fine. My warm and sometimes raced engine runs H beams because I thought they would work fine and reasonable cost. They have in fact worked fine and checked fine at freshen.

This conversation is far older than the internal combustion engine, and still no answer.