The Osis Flatliner is a good spray for protecting your hair from heat, without making your hair sticky or greasy. I guess it does help to make your hair more straight, though I am not the best person to ask, since my hair is naturally straight. I use it to protect my hair before blow drying and I can see that it makes my hair less frizzy and tangled. It also doesn't weight you hair down.The smell is weird, like alcohol, but doesn't dry out your hair. It doesn't give any shine either. I hate the spray nozzle. Most of the time it doesn't spray evenly and parts of my hair end up soaking in the product.