I have been back and forth on this for a while. I don't use a comb, but I do use a denman, and I am looking for an Aveda brush now. I use my denman once a week to detangle while washing it, and then when I am putting my twists in. I find that everything about my hair changes the longer it gets. When my hair was shorter, this was an option, but not anymore.
I tried finger detangling and my hair laughed at me I have to detangle...with a wide tooth comb follwed by my paddle brush to remove all the tangles, otherwise I've got knots and mats everywhere. I started to notice that when i detangle my hair at least 1x a week...i get less knots. I think that a lot of people that complain about the knots might not be detangling thier hair enough/properly.