We see a lot of nail polish here at Bella HQ, so it's always fun to try out something a little different. The polish du jour is Perfect Formula ($15), a lacquer with keratin and calcium to strengthen nails — like Sally Hansen Xtreme Wear Nail Polish ($3), but with nicer, smoother application and edgier colors.
It most definitely does make your nails hard. I also like the texture, which looks almost jelly-like coming out of the bottle, but still has good opacity and pigment payoff. My only concern with the paint is that it takes forever to dry. Granted, I didn't apply topcoat, but I was still smudging it on stuff half an hour later, which is a painfully long time for just two coats. So if you have weak nails, I'd say give it a try — as long as you have patience and plenty of fast-dry topcoat on hand.