I am a Personal Trainer who also teaches 10+ group fitness classes a week, so I KNOW FITNESS CLOTHING!!! :-) As a highly active person who wears through everything, I can speak very truthfully regarding these pants.

Pros:
Thickness - awesome weight to the material, not too thin or flimsy, and not too bulky either.
Stretch - you can MOVE in these babies! Your flexibility is not restricted in any way, and are very, very comfortable.
Design - let's face it, fashion is just as important as function, and hey if you look good, you feel good, and if you feel good, your workouts are more efficient; therefore; looking good = better workouts!! Hahaha, in all seriousness, these are pretty cute.

Cons:
High Intensity - do NOT wear these to a high energy boot camp or to kickboxing. You will spend the entire time hiking them up in the rear. They are not meant to be super tight and hold up with Jumping Jacks or Burpees. Yoga, yes. Jump squats, no.
See-through "ISH" - when I bend waaaayyy over for a downdog in yoga, the pants may be almost, kinda, sorta, do I really see anything? , now I am staring at my own butt a little too long... Not really see, but maybe shiny. And no one is going to stare that long at anyone's pants in a dim lit yoga studio, or really care that much to look in the first place, to make it a big deal.

Final thoughts:
Comfortable and cute, durable, holds up after heavy wear and many washes. Design is high quality. These are just not designed for high intensity activities, so don't expect a high performance athletic pant for running etc., but are perfect for everything else. Pilates, yoga, running around, I even sometimes wear these under my snowpants while downhill skiing. For the price point, you really can't go wrong! Will be buying another color soon, for my Core & More class! :-)
Cheers!

I get complements on them everytime I wear them. They are the best I own by far, the fit, the feel , and comfort are the best I have ever purchased.