I love baby legs for wearing underneath pants in the wintertime.  They prevent your child's legs from being exposed when you are carrying them in cold weather (as the pants legs always tend to "ride up").  They are useful in and of themselves around the house and make diaper changes a breeze.

While the BabyLegs Cool Mesh leg warms in the cherry "Jubilee" design are ADORABLE, their use isn't an obvious for summertime.  They do have SPF but just wearing pants or applying sunscreen over bare skin would accomplish the same thing outdoors.  They are still useful to protect a crawling baby's legs so I would still buy a few pairs of these for kicking around the house in the summertime.  I do tend to favor the wintertime BabyLegs warmers for their multi-purpose use.  But it is great to have the mesh option for other seasons (or warmer climates).