Oscar looks so cute without a beard! I love that pic of him. We have a hard time with mats on Roxy, too. We finally cut out the ones we couldn't comb out. There were still some that were right up to her skin so the bet brushed them out while she was being spayed. She looks like a little ragamuffin right now - hair all chopped in spots, but, then, so does my cat who grows mats for hobbie.
We are using Pantene conditioner now and that seems to help. Good luck.