I imagine Aristotle is going to post in this thread something like "Beauty(art) is in the eyes of the beholder. All of these men are artist, the quality of their work is totally dependant on the reader."
And it's true to a point that we can't simply say an artist is bad or sucks because we dislike their methods. We have to deem good or bad based on the point of the work.
1. Comics are sequential art. Does the artist's work tell a story?
2. Does it keep us entertained?
3. Do we feel any emotion from emotional scenes?
4. Personal Bias aside, can you tell if a character that is supposed to be tough is tough, or if a sultry woman is sulty, etc.?
5. Does the artwork fit the theme of a story?
and lastly...
6. Is the artwork worth the quality of having the backing of whichever studio they work for? For example whoever does Invincible or whatever that comic is called...sucks. They even had a spidey crossover. This is an official comic but it looks like a webcomic. Lame. I don't want to pay money for something I could draw better myself. Seriously, I could read the plot summaries and do the art better..
But as I said at the beginning of the topic, I haven't seen enough of his work to 100% deny yous guys' claims. So maybe there's a dimaond in the rough, proove Turner to be a bad artist, I'm not trying to stop you...you just haven't done it yet.