Over the last 2 years we have tried Global Keratin the original version, very heavy to use but good for really curly hair, La brasiliana, lighter but not as strong, we changed to kerastraight as this was only 48hrs before washing and really had good feedback. We changed to a product called Eternity Liss because the hair could be washed straight away and the results are amazing, however quite fumey if you overload the product, now we have gone back to kerastraight new ks complex, no fumes and same day wash- plus fabulous marketing material and support.
The bbd for us has a repeat booking rate of at least 90% now.