Indie-Resource.com

Gah people need to stop releasing so many nice engines :O
This one is sweeeeet although other than the free version the personal and business versions are a bit pricy
http://www.bluega.com/bxg-info/

Download link:
http://www.bluega.com/bxg/downloads/

It looks nice, but expensive like you said. I would like to see a list of features that would make it worth 2.5x what Impact costs, but I just can't seem to find anything on their site.