We are working on modified version of blender customized for mechanical and architects users.
We starting developing better snap tools and we continued developing on mesh dimensions, geometry, must have tools, ucs, and much more.
Some videos can be found on https://vimeo.com/user2228784
Development is shared on github https://github.com/mauge123/mechanical-blender
Also you can check http://www.mechanicalblender.org
A group forum is also created https://blenderartists.org/forum/group.php?groupid=326 You can join there for more specific questions/answers!
Thanks for your feedback!