When I still lived in Slovenia, I had 20/20 FTTH. Fiber went directly into a router in my bedroom. My bandwidth was always exactly 20/20. No matter what.

Now I have Comcast. Speedtest says I get 80/6. On Friday and Saturday evenings Netflix and Facebook and many other things often experience issues. Now I can't confirm any of this. If you run speedtest, it's fine. If you ping something, there's no packet loss. But it just doesn't feel very fast and reliable under normal use.