It depends what you need. The Cat's Meow is only rated to 20 degrees but it is significantly lighter. You should usually buy a sleeping bag that is rated to colder than you will need. If you plan to use the bag on 20 degree nights I would get the Leopard. But if the coldest you think you'll be camping in is 30-40 than I would get the Cat's Meow. It also depends on how cold you usually are, are you a warm or cold sleeper? Hope that helps.

-Jared