Ok first of all I am not a fitness buff...BUT
I have been working out like crazy and really trying hard to get into shape.  I had a pair of Nike Shox and they were just KILLING my feet!  To be honest I saw these shoes at Dick's Sporting goods and thought they looked cute and were super lightweight...and for the price I thought I'd try them.
These shoes are great!!!! They breathe really well (no sweaty feet), are fairly comfy (of course like all shoes you have to break them in a little), they make you feel like you have a little extra spring in your step....very nice all around.  The only downside to these shoes is that if you get into any rocky terrain (like we have here in CO) you'll be banging little pebbles out of the bottom of the zig of the shoe at the end of your workout.