Good stuff, a little pricy
I have very very thick and long red hair.  I made the mistake of getting highlights, destroyed my hair and became a rats nest of tangles.  Most all reviews on google mentioned Olaplex.  Price is not bad unless you have hair as thick and long as mine.  Product works great, however it’s only a temporary fix until the next wash.  It seems you have to use all the steps to get the best results, and several of the steps require rinsing after application.  So applying a step, rising, applying another step, rinsing.  If you have time for it, it’s fantastic.
Rating: 4 stars