The best thing is that they offer the whole source as well. That is something you should think of.
AFAIK the source code of the previous versions of Torque (TGE, TGEA) is said to be a mess. At least this seems to be a common point of criticism in the reviews on devmaster.net. I dont know though whether this is still the case for Torque 3D as there are no T3D reviews on devmaster.net.
The C4 engine is probably a much better choice in this regard, even if its more expensive.
