I think it totally depends on the product and your hair. Some people have hair that just looks good no matter what.
For me, I love Matrix Sleek Look, it makes my hair soft, shiny, and smooth. I will totally keep paying for it. However Matrix Curl Life hasn't done much for me, I had better luck with L'oreal Curl Vive for when I'm going natural.
Also I've used a lot of Paul Mitchell, right now I'm using the Super Skinny Shampoo/conditioner/serum. Well the serums great, but the shampoo/conditioner make my hair feel kinda dry now. I alternate my products so it's not too bad, but I def. won't repurchase.
My 2 fave drugstore brands are John Frieda Sheer Blonde and Got 2 Be, all the stuff they make works really well for me!
Also Sally's has generic versions of many products so that's worth a try!