Today I tried the Crest 3D White Whitestrips Professional Effects Impressions by occurrence: 1) Strips are very sticky, they stick well to pretty-dry teeth. However, I find it weird that they don't cover ALL of your teeth, who wants half-white teeth?? 2) After about 10 minutes of wear (out of 30) I started tasting the nasty gel-like substance they use for the whitening ~ I felt like barfing and I had a bit of a stomach ache. 3) I removed the strips, and my teeth felt smoother than usual. 4) About 4 hours after using {reason I decided to write this post} the strips for the first time, my teeth felt cold and very sensitive. The strips didn't work for me - I discontinued use. Received complimentary of Influenster for testing purposes.