What actually works for branch office SD-WAN under Cloudflare One?

Looking for real-world feedback on using Cloudflare One as a replacement for traditional SD-WAN for branch offices. The marketing is all "magic" but I need to know what's actually reliable.

Specifically:
* How stable are the Zero Trust tunnel connections (cloudflared) for site-to-site? Any chronic disconnects?
* Can you truly route *all* traffic (including non-HTTP/S) through this? Or just web traffic?
* Gotchas with on-prem devices (printers, scanners, local servers) after implementing?
* What's the actual failover behavior if the tunnel drops?

Assume a basic setup: a Linux box at each branch running the daemon. Not interested in the happy path. Tell me what breaks.