I usually have 2-3 different kinds of shampoo and conditioner in my bathroom. I found that if you switch once in a while, it makes your hair softer and bouncier! If I keep using the same shampoo everyday for a long time, my hair gets flat.
I'm a rotator too (hmmm just like bags). I admit I probably have 5-6 shampoos and conditioners in my showers. Total junkie. Rotating shampoos every day works for me. Every once in awhile I'll use Neutrogena's shampoo to really get it clean but not that often.