[sthulbourn]

Disclosure: I'm a developer of this tool & work for BBC News.

We use this for catching things that we'd never spot, a good example of how it has helped us is after a giant Sass refactor, we ran this tool against the old CSS site and the new CSS site, this showed us where things were off by a pixel or two (as well as big formatting changes).

We've found this tool rather valuable, we're not saying everyone will, or that others should use it. We open sourced it because it might help someone.

[tonetheman]

If you get a chance look at our screenshot comparison tool. We ended up using the dom elements to do the comparison. It is a different tack on the same problem. http://crossbrowsertesting.com/layout-comparisons-for-screen...

[morsch]

Thank you.