You had the option to purchase the OEM hitch with or without the wiring harness. The OEM wiring harness was a 7-pin flat. Some aftermarket harness can be 7-pin or down to 4-flat depending on your needs. I did the OEM 7-pin wiring harness and purchased an adapter to 4-flat when I need that.
Some of the aftermarket hitches do not have enough space for a full size spare (donut only). The OEM hitch can take a full size spare and has the pre-drilled holes to attach the OEM wiring harness.
Son - 06 TSX 5AT w/ Navi, Carbon Gray w/ Quartz
08 RDX Tech, Moroccan Red Pearl w/ Taupe
11 MDX Adv/Ent, Palladium Metallic w/ Ebony
19 MDX sh-sh-awd Adv Fathom Blue Pearl w/ Graystone