no offense but the real one looks better. i mean, this one looks too sluggish and bubble headed. it looks like it's supposed to be some big bitey blasty thing with barely any defense, but the real mega aggron looks like anything you throw at it, it will keep standing (which is not just provided by it's bodyshape, but also by it's spikes forcing him to pretty much stay standing), and truly looks capable of crushing anything in it's bath just by trampling them.
Ok i LOVE your mega evolution but to be completely honest I think you have gone a bit far with this one, Aerodactyl, metagross and pinsir, all your other ones look like they could have been made by gamefreak, I mean it the other ones are pure fucking gold. I hope you make more like the other and don't go as far as you did with the one i listed, they just look like they are other pokemon entirely or normal evolutions and... yeah keep up the good work and please all you people that will reply with "you hater whuah whuah" look at this comment as pure critisism and nothing else, because that is what this is.