I try and work on it a bit Plazz but have a lot of problems not making the fighter renders look obtruding, making them appear more natural is the biggest problem for me.
its all about how much time u put into it... im not near the best artist here but heres what i normally do :
first i use quick selection to get the large areas out
then i enlarge the pic to it gets really big and use a 1-2 pxl brush and go around all the edges. ( remember to have a coloured layer underneath so u see the rough parts better )
the feather effects are used sometimes by me but i dont really like em cuz i feel they sometimes "cut" to much into the pic.
ALSO and heres a personal trick of mine....the blur tool.
i know some ppl here wouldnt like using it to smooth the edges but i actually think it works nice ( it has to be a somewhat high quality pic though ) after u have brushed the edges then use the blur tool too smoothen it.
PS. too high pxl on the blur tool will make the edges give out a faint glow. there are several ways to get rid of this but the way i do it is to go over it once more with the eraser to take out the glowing "white" areas the blur might have left behind