I have tried several teeth whitening products over the years. The best working one I got a few years when my cousin was in dental hygienist school, and I was a guinea pig for some foam trays. I didn't care to wear them (felt like I was going to gag), but after one tray you saw results immediately.
I've never cared for Crest Whitestrips. And Colgate had some paint-on paste to apply at night that worked okay, but I don't think they even make that anymore.
So I thought I'd be a guppy for the new Listerine Whitening Quick Dissolving Strips as I had a coupon when they were on sale. (I saw a bonus deal of them on clearance at Target last week). My first attempt at using them I didn't read the directions first and tried to apply the wrong way, and it was frustrating, so I gave up. Then I thought I'd read the instructions first to see that they can only be applied one way. Visual pics work wonders.
Now I can apply them easily! They are supposed to completely dissolve in about ten minutes, but I don't think mine have ever fully dissolved, and I don't like a film feeling on my teeth. I've been applying before I hop in the shower, and I tend to take longer than ten minute showers. So, when I'm done, I simply brush my teeth to remove any remaining residue. I've been using them once a day for a week and can already see an improvement in whiteness!
So I would definitely recommend the new Listerine Whitening Quick Dissolving Strips, maybe not at full retail price (I refuse to buy anything at retail price though), so look for a sale and/or use a coupon!