Has anyone used Torque3D?

The Torque engine has been around a long time and was very popular in schools when it first came out. But to be honest, if you already know the Unity engine, you should just stick with that one. You won't gain anything with Torque. The Unreal engine is another popular one that is still used in the game industry.

The big difference to know is that Unity was built from the ground up to be a universal game engine. It can be used to create 2D or 3D games and can output games for Windows, Mac OS, iOS, Android, HTML5 and some other platforms. Unreal was originally built to create Epic's Unreal games. It has been upgraded and modified overtime to clean it up and add lots of functionality, but it was originally designed to make shooter-games. So in the end it will really come down to what you want to make, what skills you and your team have, and who's going to play it.

Personally, I think for a beginner, the Unity engine and community is a little more user-friendly.

Northeastern University has an entire department & manor devoted to creation of video games as well as a number of publicly-available listservs that you can sign up for. Might be worth checking out.