I have been trying to get consistent service using UMA at home, but it requires a level of service (85% QoS) that my provider (Comcast) cannot provide. I am looking to switch and wonder what are other people using?

In my experience, no residential Internet provider is going to guarantee QoS and actually stand behind it.
I chose FiOS, because it's reasonably priced, very stable, and the speeds are AMAZING.

FiOS is not available in my area yet, so it's not an option for me.

Charter cable here and it seems to work quite well. Does Comcast not offer their own VoIP? Not that you should use it, just that how can they setup a network that won't support it? Seems strange to me.

My feelings exactly John.

Hmm... OK.
Your subject reads "Cable or FiOS or DSL?" So I assumed you were chosing between the three of them.

While FiOS is not available at this time, I would not exclude a current users experience.

I hope that FiOS is available in the near future, and I would use any experience gained up to that point to influence my decision.

I do welcome your opinion and experiences as I try to make the best choices.

I use DSL and have had great results with UMA.