Personally, I like Breezebrowser Pro; it's more expensive than ACDSee, but I think it has better features. I really like the way it implements tags, for example. Yes, ACDSee implements tags, but they don't work as smoothly as BB's. In BB, I can select all my pictures and start a slide show (ctrl/A, ctrl/S). Then I do another ctrl/S to pause automatic advance. Anything I want to tag, I hit the up arrow. Un-tag, hit down.
I use this to quickly find all the trash files and delete them. Then I go through and tag all the ones I like and want to look more closely at.
There's also the ability to "rank" images, and then select or tag all the images that have a certain rank.
And it handles RAW images, and can proof your images (different size, auto-levels, etc), and can produce HTML pages.