I have to say I agree with DarkJames completely. Not to put down FPSC since it's very good at what it was designed for but the simple fact is it wasn't designed for making commercial grade games. It says as much on the website; you won't make the next HL2. Now of course there are some people or groups of people who push FPSC to the limit and kudos to them (EFX mod was pretty impressive) but the thing is for all the time and effort that was put in, had that same effort been put in another engine (say Unity 3), a real and more to the point
original game could have been made (literally hundreds of indie games have been published with Unity, including for the Wii, many for iphone). Again not dissing FPSC since it's still great for hobbyists and great as an intro to game design (it's what got me started). It's just that as far as publishing goes, you're likely to be limited.
For example, yeah you could make an insane painting like the Mona Lisa (or whatever) in MS Paint...but had you put in the same effort using something like photoshop, it'd take you less time, would be easier to do and probably turn out better. MS Paint is definitely simpler to use but also more limited.
To put it another way, if you REALLY want to make your own game you have to learn programming, modeling, rigging, etc, yes? And as you go learning all this stuff, you start to really see the limitations of FPSC. That's basically why I don't use FPSC much anymore (I'll still play with it occasionally) in favor of Unity--Unity and UDK are optimized for the people who do programming, modeling, rigging, etc. FPSC unfortunately isn't or isn't enough. (which is why I don't bother porting my characters for FPSC; they're fully rigged and animated and everything but the effort of getting them ready is just way too bothersome)
Not to take away from FPSC though because you can make/sell games with FPSC; it's just not as simple as it seems. Making a game that's good for FPSC isn't the same as making a game that's good on any standards and I think that should be the aim if your goal is to sell.
/end rant
(btw, I'm very interested in hearing other peoples opinions on this matter)
edit @ PaYaM
If I understand correctly, you got a one-time $500 so your publisher could use your game, yes? Even so that's still pretty good all things considered. That's more than a lot of people have made from their games here. I find it really interesting too that Iran is trying to build up it's game industry; I'm from the Dominican Republic (live in california) and they're trying to do the same, though it sounds like we're far behind Iran at the moment.

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