I used Infusium 23 Leave-in for 15 years.

I could never get my hair to grow past BSL and would always have 1-2 " cut off every 4 months or so.
Then I found LHC and learned about how cones work. I quit using the Infusium and started using jojoba oil and aloe gel instead. In less than a year, I have very few split ends and my hair , at it's longest layer, is waist length. I haven't had a hair cut, or micro trim , since October, 2005.
I rated it poor on ease of use, because it was so thin, I had to put it in a separate spray bottle to use, or else waste alot of it trying to get it in my hair. It's not priced too sweet either. I find using one of my regular conditioners as a leave-in and on the ends, works much better and it's cost friendly.
I'm not bashing cones, because I know what works for me, might not work for someone else. I like the water soluble cones and now that I know I can clarify using an SLES shampoo, diluted, gives me a wide range of products to use.