I've never come across a geocoder better or cheaper than Google, unfortunately. They all claim accuracy but fail in trivial cases, or interpolate to the wrong part of the street where Google is spot on (though Google has its occasional flaws). I'd love to see competition but it's probably not coming any time soon.
A comparison is challenging in that in our experience there are many different use cases. It all depends on which geographies you are interested in, and what level of accuracy, speed, data freedom, and cost you are willing to accept. I mean of course we can do query X on different services and say service A returns answer 1, service B returns answer 2, etc. But that's only useful if your queries look like X, and very often they don't. So it's difficult to say "service A is better". Much more relevant is which is better for your specific needs (and budget).
The only guaranteed way to know if a service will meet your needs is to test, hence why we offer 2,500 free queries per day for as long as you like.
