Here is my feedback after testing out a 24" Cintiq touch over the past several weeks. I appreciate all the responses. They swayed me to give it a try.
I honestly did not expect to like the Cintiq since I have become so accustomed to using the tablet-to-monitor process over the past 10 years. However, I was dead wrong. The experience is surreal. I felt like I was drawing in my sketchbook, except I was using my Corel Painter tools. The process is so natural you forget its digital. It proved to be much faster for me than the tablet. I like a lot of detail in my art and it can be accomplished much quicker on the Cintiq. The reason for that is because I zoomed in too much when using the old method. With the monitor being two feet away from my eye, I over compensated to get a closer view of the details in my work. On the Cintiq, you are right on top of your work. It is easier to accomplish those same details without zooming in as much and working on a larger area goes much quicker, at least for me. A good example of time saved would be an average, full-blown, illustration would take me about two weeks the old way, I am finishing the same illustrations in 3-5 days on the Cintiq.
As far as the eye strain, I did feel it as I worked on the Cintiq for the first few hours. My solution was to remove my glasses. I am nearsighted, but not so much that I need glasses to work in my sketchbook or the Cintiq. I have worked daily on the Cintiq with no noticeable eye strain for several weeks now.
I will also add that I recently upgraded my Power Mac with a MATTE monitor (Apple Cinema Display) to an iMac with Retina display. Like many digital artists, I anguished over the fact that Apple no longer offers monitors with matte displays. However, I was pleasantly surprised to discover that the glare on the iMac is pretty minimal in my studio. (Please note: My monitor faces the interior of my work space.) If you have a window behind you, it may result in a distracting glare you can't get past. My studio does get some late afternoon sun and the monitor will pick up reflections from the sunlit desk. It is nothing major, but noticeable. Apple does allow you a 14 day window to test a product and return it with no questions asked. I planned on returning it and purchasing a Mac Pro w/ Dell monitor if the iMac didn't work out. I'm happy to say it did. Much cheaper.