Which is stronger, I-Beams or H-Beams? It depends whom you ask, and the relative weights and cross-sections of the rods. I-Beams can be just as strong as H-Beams, but H-Beams can often handle higher compressive loads than I-Beams with less overall weight.
Consequently, H-Beam connecting rods are often recommended for high torque motors that produce a lot of power at low rpm (under 6,000 rpm). Some rod suppliers offer H-Beams as their “entry level” or less expensive line of performance rods, and offer I-Beams for all of their high end racing applications. Other suppliers only sell I-Beams, and some only sell H-Beams.