quick list building is easy. I like being able to grab 40-50 contact names in under 5 minutes and send them to Sales Force.
The information is really outdated. Sometimes I find names of people that haven't worked at that company for over a year. Also, I would prefer being given no contact info rather than wrong contact info. Other tools will not provide an email or phone # if it is not verified. I find data.com to do a lot of guessing when email addresses are not verified.
Data.com is helpful as an additional source/tool for verifying contact info if you cannot locate a phone # or email address for a contact, but I would not count on accuracy 100%. It is good for quick list building in bulk, but you will need to cross reference with other tools (ie. LinkedIn, Zoom info, etc.) to verify that people still work at that company and contact info.
I'm in outbound sales. Bulking up prospect accounts with as many contacts as possible is crucial.