Does anyone use Retin-A micro or Renova? Currently, I use differin gel for my acne, but it's really drying on my skin, esp. in the winter. Wondering if a different retin-A product would work better for my dry (and also acne prone) skin. Any thoughts on Retin-A micro or Renova? I heard that insurance doesn't usually cover Renova, since it's for wrinkles, rather than acne.