well like i already said , with 3DGS you can produce great things ,
it ony depends on your artist talent and good coding,
look at metroid 2 on gamecube , no bump mapping , simple textures , but very great,
with 3DGS this studio would use tricks to bypass limitations and
they could bring metroid2 to 3DGS like in gamecube version and same quality,
with bump mapping for characetrs creatures and some parts of the level.

And 3DGS is the most fast and easy of use of all 3D engines in the same
order of price for us , and you can quicly produce something playable like a prototype or a real game than any other 3D engine.
For example an Arkanoid game or simple FPS could be done in one hour of programming/testing in C-script ; after that it will take more time to bring it to a good level with better design, 3D models ,textures, etc..