Trying to see if this is a good or bad idea...
i have access to a full set of leather seats from a 2016 max and thinking of ripping out my cloth ones for these. Is it a simple swap? The S did not come with heated seats but I'm guessing there is a way to rig a switch to the panel...maybe? Not sure what else I might be forgetting like airbags or whatnot. Anyone done this yet? Thanks

I have Katzkin leather in my Max S and the interior is beautiful. I opted out of heated seats when getting this installed (had it done by a third party) out of concern for what it would do to the fit and finish, but it's definitely possible.

I installed my own katzkin with degreez heated seats. I have never done such an install. I did it over two days, two different weekends. Katzkin leather headrests go over the cloth, the cloth is not removable on the headrest.

heated cooled seats is achieved with a Thermo Electric Device. (Blower) This was the most difficult part of the install. You will want hog ring pliers. I re-used all of my hog rings. I took them off with some snap ring pliers that help me separate them. Probably much easier to simply cut them and replace with new. Their are essentially no instructions, it is pretty self explanitory.

Do not start your car with the seats removed, or else you will need to have the dealer reset the airbag light.

Other than how you are going to handle the headrests, I say go for it.