Not worrying about QoS setting

If my voice quality seems adequate for me, is it best to not worry about configuring QoS settings in Ooma device settings?

There's good Ooma documentation that describes the background on QoS. My speed test shows 2ms jitter, and adequate down/upload speeds. I see there's some discussion of QoS in this subreddit, but not a whole lot.

I realize that much depends on how other devices are using the shared internet connection but so far, I haven't encountered any problems with voice quality. I use an Ethernet cable between the Telo and the ISP modem.

The cable modem/router combo does not provide for any QoS settings, and it's not possible for me to put the Telo between modem and the router, since it is a combo device.