The A8 5550M APU is bit better than A10 4655M but the GPU in 15-n201ax and 15-n007AX are also better than the rest of 2 laptops. Expect the 8670M to be between 15-20% faster than the 8570M. 8GB RAM is sufficient for gaming purpose.
Honestly none of these laptops are completely perfect but integrated GPU and dedicated GPU in G505s can be crossfire to provide bit more performance and 16GB RAM would also be helpful in editing purposes.
Thank you for replying me...

Actually that was not the laptop... Sorry....
What about this? Lenovo Essential G505s (59-380146) Laptop (APU Quad Core A10 5750M- 8GB RAM- 1TB HDD- 15.6 Inches- DOS- 2.5GB Graph) (Midnight Black)
http://www.snapdeal.com/product/lenovo-essential-g505s-59380146-laptop/1720865281
And now i have another laptop in my mind... Lenovo G50 (8GB Ram, Ci3 Version)
What about these two?
Overall performance of G505s will be better