/cgl/ - Cosplay & EGL

I have almost hip-lenght hair. It's completely healthy and thick, the only problem I have is that it's frizzy as hell. I have tried tons of products and nothing help it.
At my local salon they recommended me two treatments. One is a keratin treatment (by a brand called Kerapremium I think) that last 3 months, straightens and reduces frizz. The other by Mucota, that is a permanent straightening treatment, lasts 8 months. Has anyone tried them? are they damaging for the hair?

Have any of you tried brazilian keratin hair treatments? In my local salón they offer one by "Kerapremium" that is supposed to straighten your hair for 3 months and in general make it prettier but I'm scared it wont really work or end up bad, couldn't find a single review.