I use Babyliss Curl Secret. It is very amazing, It can be up in braids all day long and will fall out without a kink.
Yes it is amazing, and yes it takes a bit longer to complete a full head of hair than using an iron.
I bought it from www.haircurltool.com. It is the cheapest I found. The price only $109.99 and I found a coupon code BABYLISS10. So it only cost me $98.99. I love it so much because it curl my hair very well. If you love to curl your hair, it is really a perfect one.