I've been following this project for quite a while. It's a very nice little modeler that was built to please the Silo crowd. Originally it was called VoidWorld, but it's since been renamed NVil (anvil).
For the longest time it was available for free as a beta, but he's now selling it.... for $79.http://digitalfossils.com/
Head to the forums for more info: http://voidworld.cmcproductions.co.uk/
Overall it's very fast, and does exactly what a modeler should do. The developer reminds me a lot of Andrew Shpagin the developer of 3D Coat, in that he is extremely quick to reply to feature requests and releases several updates per month.