Nevertheless, it's simply a matter of taste in the program. What program you use will affect the quality of your image, that's dependent on your skill with the program. Photoshop can do anything that any other program can do, seriously, it's as good for painting as it is for altering, and for someone like me who's been using it for nigh on years (seriously, my art program chain was a straight shot from MS Paint to Photoshop) the thought of parting with it is unbearable, and I'm sure that there are many other artists like that.
You can't really say that one program is better then another, you can simply say that you're better at using one program then another. And that's coming from someone who's a die-hard PS enthusiast who spent years laughing at Gimp (and I still am, I suppose). Corel Painting is not suited to altering images, it is suited to painting. So if you want to take the time to learn the program, then by all means go ahead, I'm sure you'll produce a few great pictures. Just don't go using it for anything other then that, because it's not designed for that. I won't begrudge anyone their choice in program, or their choice to roam around testing new ones.
But learn it quickly. It took ages for me to unlearn enough stuff from PS CS2 to be able to use PS Essentials, dammit.