Doubt with s905 / s905x for Libreelec

I bought my parents (almost eighty) two boxes for live tv. They now have a server under the roof and watch tv via kodi + dvbviewer plugin. It´s stable enough now.
You should consider a third party remote - or even better - check if cec is working good with the remote they already have.
The boxes often have problems powering up and down via remote - that would be a big problem. The good thing with cec is, your tv will power on the box, and shut it down when switched of.

The first few weeks my parents had trouble with this setup, and I still need to explain and help from time to time, but overall it works great. You have to put some thinking into the configuration, before giving it an elder person - what does he/she need, how do to configure the box that everything works as intended. And test it yourself for some days.