For sure the lite-c isn't too complex.
If you compare 3D Gamestudio with other engines, well, it is not realtime (like one engine LordMoggy(?) posted before). Yes it was an AAA engine. There are still some bugs, that's why people think it isn't a good engine, but "WHY?" - Do it yourself if you think it's bad (and if you think you can do it better!)!
I don't know other hobby engines.
The prices are good, too, compare what you have to pay for a AAA engine - so you can't compare

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Another thing: It's only for the Computer, no Wii|PS3|PSP or XBox360 support - This could be improved

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The manual is great - you can learn many things from it.
Yeah, there aren't many tut's, but are there many tut's for other engines.