I haven't used Painter Essentials 5 or Mischief, so I can't say much on either of them. The ability to zoom in forever does sound pretty neat though, I'll admit.
I use a combination of Photoshop CS6 and SAI. I like using SAI because of the built in stabilizer it helps for line art, since I've got an unsteady hand. I switch between the two since they both kinda work together (ability to save in the same formats, psd). Most of the time I use SAI for the initial sketch and pen work. I like using Photoshop for coloring though, since I'm much more use to it for that sort of thing. Although I'm sure SAI can do some pretty neat stuff regarding color, I just prefer Photoshop more, again since I'm just more familiar with it.
I've tried ArtRage Studio (it came with my tablet). Its alright. I can't seem to wrap my head around the interface though. The coloring ability closely mimics traditional, and it comes pre-loaded with actually useful brushes that look pretty realistic.
I've also tried to use Clip Studio Paint, its a really heavy piece of software, so unfortunately I get some severe lag. However the features are really cool, you can get a 3d model and pose it for reference within the software. The inking is top notch very smooth and crisp lines. I like the interface, it has elements that are similar to Photoshop, but still has its own unique features. Shame my pc isn't strong enough to handle it so well.