Pandora streaming audio for Droid phone- bandwidth and use danger?

Hi folks, don't know where to ask this, but this subforum seemed good as any.

I downloaded Pandora radio for my droid phone, and have enjoyed hearing new sounds and acts streamed into my morning and evening commutes-- interrupted periodically by ads.

I'm liking it so far, but I'm wondering if I'm going to run into data use issues with Verizon (my cell/data provider), even tho I'm paying $30 a month for unlimited bandwidth on the droid phone. I've heard stories about providers pushing back against the heavy streaming users in various ways.

Should using non-stop streaming a couple hours a day bump up my use to levels where "unlimited" plan might not really be unlimited, and I get socked with some additional use fee? I wish there was an easy way to track down fine print on Verizon's site, but no...

I'd like some assurance on this before considering $36 a year for the streaming without the ads.

thanks