Dial A Smile Professional Whitening Kit $79, Retail $399

I just found this awesome teeth whitening product from Whitening Lighting that takes off SHADES within the first session (20 minutes).  I tried it and went 2 shades lighter.  I asked my husband test out (so I'm not seeing things) and his teeth went 4 shades lighter.  Our teeth felt fine afterwards, and NOT sensitive at all.  I was worried about it leaving my teeth feeling sensitive like the products I used to buy from my dentist.  

This product has been seen at award shows and featured in magazines such as US Weekly and In Style.  Did you know that white teeth can make you look a few years younger? 

Dial A Smile Professional Whitening Kit (CLICK HERE) is listed for $399 (ouch, right?), but use this code: SMILEKIT and save $320 = final price $79 plus $7.50 for shipping within the US. 

What product(s) do you use and does it work?