I bought a couple of Forever21 tights in different colors, and so far I am happy with my purchase. Although they are not as good quality at American Apparel tights, they are pretty ok for the price.
I agree with the last review - they're not the greatest of quality but you have just got to be careful with washing them and catching them on things - same goes for every pair of tights really!
They come in a great variety and they're not too expensive. I don't like to spend a lot on tights because they can rip so easily and I won't wear the crazy colors with everything. Forever21 stocks a great variety of patterns and colors for cheap. They're obviously not the most durable tights but if you take care of them and only wear them every once in a while they'll last for a while.