Is there a reason to not use google's DNS servers?

I live in the US, using Comcast's internet.

The fact that comcast can see my browsing history bugs me. A lot.

I realize that I'm basically having google see it instead of comcast, however google gets it anyway (I use chrome, I use google search, gmail, youtube, andriod, etc...)

I also use a paid VPN, nVPN.

Is there a reason to not use their DNS services? I don't notice any speed changes.