All in all I am very pleased with this kit. I smoke and drink daily so it really took a toll on my teeth. After two applications I saw a noticeable difference! Pros: Easy to use, quick, tastes good, effective Cons: My gum's really did hurt after the second round. It was almost too much to handle. I stopped at two, and reapplied the next day, and the day after and it did the job and I still have left over applications. I started with one tube top and one tube bottom and I think it was too much. It overfilled and therefore was touching the gums too much. I wouldn't recommend using this all in 2 hours, your teeth will hurt way too much. But after a few days applications my teeth look great and everyone is commenting!!!

Product was used as instructed, but burned my gums. 1 day later and I am still experiencing painful gums.

I followed instructions but tray melted into an unusable mess. But I liked whitening gel.

It is not as harsh as I have read about, but I have not had the time to do all 4 treatments in the same sitting. It works better than other whitening products I've used. I like the trays, they go above the teeth so the product reaches up to the top of the teeth where it is yellowest. I would recommend this product product for anyone, but if your teeth or gums are sensitive to it, just don't use it as often. Maybe skip a day, etc.

I was not impressed. I barely noticed a difference. My teeth still seem to be a creamy off-white color to me. I might try the i-white instead.

Product was used as instructed, but burned my gums. 3 days later and I am still experiencing painful gums.

Really great!

I had my teeth professionally bleached 6 years ago at the dentist using custom made trays and whitening gel that you take home and use. I decided to use those trays with the Rembrant 2-hr whitening rather than the ones it comes with. I have a small mouth (contrary to what my kids say) and the Rembrant ones were still super loose even after I molded them onto my teeth. So I used my professionally made trays. The 3rd application and my teeth were starting to get that numb sensation like when you eat something super cold. I wondered if I'd be able to go ahead with the 4th application, but I did. Results were as good as the dentist! (which cost me around $425 if I remember correctly) I only used one vile at a time for both top and bottom--again, I guess a small mouth saved me some money. So I have 3 viles left--would have had 4 but the first time I filled my trays I used 1 vile per tray which turned out to be way too much--gel oozing out the top/bottom, etc. The roof of my mouth is still a bit sore an hour later but no pain while eating, etc. I'm glad I tried these and will use again in the future.

This stuff is just amazing! I was considering using the Crest Whitestrips, but then I found this, and I thought it only takes 2 hours, why not? I read most of the reviews of this product, and I saw more good comments than bad, so that made me want to try this more. As to the pain and discomfort, the extent of my pain was a barely noticeable tingle. I only used 3 tubes and I have a significantly whiter smile (I didn't have yellow teeth, but I just wanted that extra pop of bright white teeth), and I also used one tube for both the trays per application. The trays were extremely hard to mold to my teeth, I pretty much just gave up trying after the 4th time. My biggest complaint was that I had so much saliva in my mouth after the 20 minutes that I just thought it was gross, but for my results I can definitely endure that again. I love this product, it's just awesome.

These are better than the disposable strips but I found them quite painful and after the third 20 minute application, I only barely saw a difference. Forming them to my teeth was easy but they aren't kidding when they say not to leave them in the hot water too long. You'll ruin them if you're not careful. As for the whitening solution, I found it impossible not to get it on my lower gums and it was super painful, like it was dissolving my gums. I don't drink coffee, but I'm a soda drinker so maybe the dye in soda is harder to remove than coffee stains because the change is so minor I'll finish the fourth application on my top teeth and then I may not ever use it again. You can get about two 2-hour sessions out of one box though because one ampule is plenty for two trays. Even using less than half an ampule on my lower teeth still caused major burning. So, a star for the cool trays that mold to your teeth and a star because it worked for my sister.