What is the best brand of keratin hair treatment?

I have curly hair, I'd like it straight.What is the best brand of keratin hair treatment?
I use a seller of a brand called ';OK'; from a seller called besthair4u or something.





Anyway, it's $39 and my hair is just a little past my collar bone and the bottle is enough for 3 applications plus there is a bottle of shampoo that comes with it.





By the way, I don't follow the instructions to a T. For example, I don't always have time for the 2 to 4 hours it takes to do the whole process. So, I tried washing my hair the night before and letting it air dry.





The next day, I add BKT and let it air dry again and then straighten it later.





The results are EXACTLY the same. I have been telling everyone.





I find that no matter if you get the regular, chocolate or pineapple, it stinks all the same.What is the best brand of keratin hair treatment?
watch out for the brands that might contain formaldehyde!!! just an FYI!!