I like how they are able to give us some data about what we're buying, with no hidden fees or surprises after paying for it! We don't see any downsides either as far as pricing goes (you pay per impression).
The only thing would be if you want more reporting than "where did people click" -- but there's nothing wrong really other then just wanting less information from them overall compared to competitors who might offer additional options in this area? This tool works well because of all our impressions being tracked very closely by bidera itself so its easy when doing your own analysis/reports later downthe road - plus since everything stays within one account at times makes things easier too especially wen sending out reports internally across companies etc..