Replying to Which Camera? Canon 5DS or Mark IV?

So I'll be saving up to buy one of these cameras. I shoot mostly photographs so the 4K video with the Mark IV wouldn't be necessary, but would be nice to have for the future when I start to venture more into videography in the coming years. I currently have no experience with video production. I'll be going to school for Multimedia Technology, which is an ensemble of photography, cinematography, business, advertising, graphic design, web design, among a few other things. I'd like to someday work for an outdoors company (Outside Magazine hit me up please for an internship) doing marketing for them. I'd also like to do some of my own personal landscape photography and sell prints, so the 5DS would be nice with the 50MP sensor, that way I could make massively large prints and not have the quality degrade much. Would the 30MP sensor on the Mark IV for sufficient for making large prints? They're both $3,500 dollars for the body. With the 5DS I'd have the option for shooting cropped pictures at 1.3x and 1.6x.

For the photographers out there, which would you choose if you were planning on shooting primarily landscape photos with a chance of selling prints?