Only had brief references as to whether it works, no indication how to implement.

Which base stations?

Is a client who is accustomed to the Xfinity voice commands going to watch me set this up and go, “Wow, this is really lame!”

You don't need a base station. The remote has WiFi and connects/controls the Xfinity thru IP, straight from the remote.
The setup is all done thru the remote's menu (CCP is not involved).
You do have to do some things to the cable box first to get this to work. There is a tech tip on the dealer site about it.

I haven't set this up for anyone yet, so I don't know how well it works. But it connects just like the OEM Xfinity remote does, so it should work just as well.

I have a 1400 on my desk, waiting to set up with my daily driver system. Hopefully, trying to make some system changes after the Superbowl. I'll still keep Xfinity around for a bit to test the voice feature. I can report back...

A couple things on the MX-1400... I recently added the 1400 for my daily driver TV and an 890 for my home theater. (I've been mainly doing Pro Control and C4 the last 5-10 years.)

The 1400 voice works for both Alexa and Comcast. Many others out here may the trick, but I could not get both options to work at the same time. I had Alexa working through the remote, but when I went to add the Comcast, it was a no go. I don't care about Alexa and I wouldn't sell the remote for that reason, so not a big deal for me.

But, on the Comcast, setting up the voice was very easy. I already had the Arris 4k box set up to do IP control from having C4 in place. I believe you'd have to go into the service menu and turn that feature on when starting fresh. The MX-1400 is a wifi capable remote, make sure to set that up initially. To add the Comcast box I had to go into the remote menu and pop in the IP address. It worked almost instantly. I was pleasantly surprised! (most of this is in the manual)