First, count yourself very lucky. Comcast users in urban areas can't get anywhere near that speed.
Second, Biggiesized is totally correct, but I personally can attest to Comcast's forgivable customer service and Verizon's very unforgivable customer service. Verizon has more bandwidth for HD channels, which is of course great. I can consider the responsiveness of the service to user inputs as about equal. Cablevision, by comparison, is the pits for user input responsiveness.
Also there's the question of perception. Will you see the difference? Dunno. Also keep bundling in mind, and required contracts. I remember Comcast having no contract agreement and Verizon jacking up the FIOS and TV prices if you don't sign a 2yr agreement.
Find a friend who has the service. Only you can judge.