For dead simple failover, I have had great luck with Ubiquiti Dream Machine Pro and SE. Not a ton of customization, but it is very reliable and quick to manage the failover seamlessly.
Have been running at a few sites and my home for over 2yrs.
When I moved to my new house and had to get Comcast, I too hated the idea of using their modem. I have always been an own my own equipment and just give me straight internet kind of guy.
That said, I have been using the Xfi deal in bridge mode with their extra wifi disabled and it has been...
You login, input the new SSID and Password, hit apply, will be disconnected and then reconnect to the new SSID like a new wifi network…
Has literally been this way since they very first home wireless aps
Very normal. Cell Phones do not get their own Public IP in most cases, they are usually clients on the Cell Phone providers network and employee different levels of NAT, routing, etc.
So again, I will repeat, normal gigabit links in a PERFECT scenario (like lab perfect) max out at ~940mbps. To go above that you need to use the 2.5gb link port that the XB7 does have (its the one with the orange line) and equipment that can run at that link or higher all the way to your device...
I believe that is the XB7
https://www.xfinity.com/support/articles/broadband-gateways-userguides
So to be clear, you are bumping up to real world rate limits on wifi and 1GB hardwire. Hardwire 1gb in a perfect world is 940mbps.
I always find this funny, because those speeds you are getting are...
I usually like to use my own equipment, but with xFi have the White Advanced Gateway (XB7). It has been flawless in bridge mode with my Unifi Security Gateway (Router).
You do realize there will be no noticeable difference right? 940 is ridiculous as it stands and you will mostly be bottlenecked by other providers when doing downloads, etc.
I have been liking the Ubiquiti G4 doorbell, but note it is part of their Protect system (ie you need to setup a device with their NVR controller software).
For wireless chimes, I use the HoneyWell wireless chimes and their wired to wireless bridge.