Install Adobe DC Pro when Adobe Acrobat Standard XI is already installed?

Greetings!

I have a scenario where a customer is running Adobe Acrobat Standard Xi on a Citrix/Terminal-server.

Now they want to install Adobe DC Pro on the same server, which should be used only by one user.

When I run the Adobe DC Pro installation it prompts telling me that it is not recommended to have these programs installed at the same time on the same machine. But there is an option to choose "ignore".

I've googled and read this article: Using Acrobat X, XI, and DC on the same machine

And also this: Acrobat DC uninstalled Acrobat XI | How to get Acrobat XI back

But I'm still unsure how to progress.

What is the downside of having this two programs installed?

Which function will be/might be troubling?

Thanks in advance.