I have several - the ones that my husband and I use total about 8 bath towels. Mine are purple, and his are mint green. The old towels, I rip up some and use as rags, and I save the rest for the doggy.
I replace them as needed. The ones we currently use are Northern Nights and very durable towels. Probably the best brand I have experienced, surprisingly.
Books are cool, but knowledge without mileage means nothing.