I totally disagree about it not being “true 3D”. It is 3D in every sense. It just doesn’t have all of the amenities of a modern first person engine like Unreal or CryEngine, but it is more than adequate for things like 3D puzzle games.
OIMO.js physics works great! I found it more intuitive than the work I’ve been doing for the past 3 years in Unity’s implementation of PhysX. Kudos to Quazi for the great job he did with Q3D’s physics.