I just use Dr. Bronner’s. It has a very short, natural ingredient list, a low amount of fragrance that is natural and easy to tolerate, and my hair gets plenty clean.
I’m not sure that works out to be cheaper, especially if you can get the soap in bulk (refill a bottle).
I am sensitive to the synthetic amalgam of proprietary chemicals known as ‘fragrance (parfum)’, and I have to evacuate the house or create major ventilation when anyone showers with a shampoo like Suave. I also then prefer not to go near their head for several hours.
It is odd how those shampoos work, fragrance wise. What I observe is a wave of odor that is emitted from the bathroom and slowly creeps through nearby rooms after the door is opened following showering.