I agree with karezone. Your hair will let you know when something isn't working or isn't quite right. I personally think regular deep conditioning along with a leave-in is essential to the health of our hair. I've been deep conditioning and using a leave-in every week for about 3 months now and after my last touch-up about a month ago, my beautician commented that whatever it was that I was doing, to continue doing it because hair was in great condition. I mean, my hair was healthy before, but the consistency with deep conditioning and using the leave-in up'd the health a couple of notches. Needless to say, I will forever deep condition and use my leave-in every single week.
What I use for deep conditioning: Mizani Moisturefuse, LUST, Elucence Moisture Balance Conditioner, and a teaspoon of olive oil all mixed together.
Leave-in: Elucence (above mentioned) diluted.
HTH