There are a few very good filters in the complete set. The sliders and advanced feature to control highlights and shadows in many of the filters are super. I have about a dozen in there that I would not want to do without. You can paint on the effects via automated layers to selectively work with an image and really speed things up.
Check out the reviews on the Nik site and look at more reviews like
This OneYou can find other reviews and info. I like them. Darken/Lighten Center, Graduated Neutral Density filter, Pro Contrast, Sunshine, Skylight, Paper Tones, the B&W converters, Midnight, Monday Morning, White Neutralizer, Soft Gold Reflector and many more I am not thinking about right now are useful either often or at one time or another.
I don't like the small previews but I do like man of the features.