Well bikkebakke, as a test I would say it is quite good. The most important thing to make clothing work fine on the game is to keep the original model mesh structure, that means selecting the polygons from the character, duplicate them and then slightly separate them from the character. From what I see, that is what you did here, so I guess it would work fine.
However, for shirt and pants it would be easier to paint texture directly over the character. Anyway, you could make the shirt longer and turn it into a suit maybe. But don't bother in modelling the pants and the shoes if it can be painted on the character.
