This is going to come down mostly to personal preference and to the condition of each camera. And maybe also to where you are coming from now. The two cameras have a very different user interface and important differences in the menu structure. For me, the choice would be both firm and immediate. But I suggest that you access Nikon USA or Nikon Canada's website. Look carefully at photographs to see how the control layout differs. Access or download the User Manual for each camera to see how the menus differ.

I also suggest looking at the lens compatibility chart. Nikon's, not some expert's. It's here:

https://www.nikonusa.com/images/learn-explore/photography-techniques/2011/which-nikkor-is-right-for-you/media/nikkor-lens-compatibility-chart.pdf

Finally...I do not know what Nikon Canada's current support policy is. I know that in the US, the D500 is still supported for now, the D7200 is not.

After finally getting the Deco Mesh to work with the new modem yesterday, I have great reception all through the house with just one of the three units working. Since I didn't activate all three when I was doing the setup, it seems that I'm stuck with just one unit. Some Decos can use their individual apps to add units randomly, but not my S4/SC1200. The model number is another odd thing. It says "AC1200" on the label, but it's basically an "S4," although it doesn't say that anywhere on the unit. They seem to use both model names interchangeably.

Maybe I'd need more units if I had lead walls or a four-story basement. As it is, I like having just one network name, rather than the three I had before.