Great work and especially good lineart. I suck a t doing clean lines.
If I should try to crit something I'd only experiment with the brightness of the background, if you could make her pop out a little bit better, but apart from that, it's perfect. ...Ok, maybe the guns looks a little flat, too. ^^
This remains my favourite. Applejack is awesome and cowgirls are awesome, and cowgirl applejack is all of the awesome, and you executed it awesomely.... that and whenever I look at this image, slinger's song from the bastion soundtrack is on loop.
Now all we have to do is wait for the pinkiepie one!....... Yep, that one will be coming super duper soon I'm sure! I cant wait to see it!