If I did not already have Photoshop 7 I would purchase Picture Window Pro. I don't know why more people aren't using this program. In some respects it is better that Photoshop. You can edit 16/48 bit images, it uses much less RAM, you can compare results as you go, and like photoshop it supports all ICC profiles and the price is $89.99. They have a manual in PDF format instead of buying hundreds of dollars of books like I did for PS. It is a professional program. I use PS-7 because that is what I already have and I don't have the time or inclination to learn a new program, especially since I have many many hours of learning in PS. Also, PS is the industry standard. I'm sure Paint Shop Pro and some of the other programs are very good, but if you are a professional, or at least want professional results, Picture Window Pro and Photoshop, in my opinion, are the way to go.
You can download a trial from Digital Light and Color at:
http://dl-c.comI came across this program at Norman Koren's website: www.normankoren.com
He has some VERY in depth studies on color management and digital photography, not to mention some beautiful photography from Boulder, Colorado.
Hope I have helped.
Robert