fix+ is good for making your skin look less dry under powder like Life In Return said, but I notice it makes my already oily skin look oilier and feel weird. It's good for use under liquid make up though, you don't need to use as much. it's also good if you can't get your hands on mixing mediums. i spritz my blush brushes with fix+ before applying, and it makes them go on more natural-looking.

i've never used Smashbox Call Time, but their Photo Finish Foundation Primer is AMAZING.