I certainly understand the merits of having a remote with a harness. However adding some feature for any unit is not a simple matter of adding a relay. The electronics of the unit have to support such additions. A system such as the defroster requires a pulsed ground. Anyway I wasn’t suggesting that such a remote does not have merits. Plainly anyone can see the advantages. I was just trying to suggest that thoroughly researching your projects is important before deciding. If a person has no interest in research or if the ease of installation is more important than additional features than that is fine. Your choice.