I have had dandruff since I was a teenager and have always had to wash daily or every other day to control it. I have very thick, very long, curly black hair (so there's no way to hide flakes). When I want to straighten it out I can't wash it frequently or the curl will come back once it gets wet. So I needed a shampoo that would allow me at least 3 days (straighteing takes more than 3 hours so I have to make it last!)
I've tried to original T/Gel, but I'm not even sure if it worked well, I just know that I can't stand that tar smell. I used Pert Plus Dandruff control for many years, but that one held off the dandruff for the day or two....which was better than a regular shampoo or Head and Shoulders that doesn't work at all. I also used Nizoral on and off. It worked great, but would stop working after a few months...I'd switch back to Pert Plus for a few months then go back to Nizoral and it would work again. I also tried Pantene's dandruff shampoo...it smelled great, but didn't work a bit on the dandruff.
So, I found Neutrogena T/Gel Daily Control a few years ago and I'm so pleased! It holds off the dandruff for 3-4 days and it smells good!
The downside is it is supposed to be a 2 in 1, but I ALWAYS use a separate conditioner (did it with Pert Plus as well). My hair needs a lot of moisture and the 2 in 1's don't moisturize enough.
The other downside would be the price. It's not bad, but for a drug store shampoo I'd expect it to be a bit less expensive for an 8.5 oz bottle.