My drawing hand was wrecked when I first upgraded my copy of Manga Studio 4 and got some fancy colorin' brushes for it, but after the sore ligaments healed up (and a few days of learning how the program ticks), I have to say it's really aces. I'd still want to do postprocessing in Photoshop because oh gracious, but if you do digital painting/coloring and want something that supposedly inks as well as or better than Paint Tool SAI, I highly recommend.

Also: if you get new furniture for your computer, for the love of Pete make sure your chair is the right height and you have proper wrist padding. Otherwise you're going run the risk of being unable to draw or game or feel like a human for a few weeks. Don't make my mistakes!