Do generic brand teeth whitening strips work as well as the name brand?

I've noticed in some stores they sell a generic brand option for teeth whitening strips, and they're a lot cheaper than the name brand kinds. Do these work as well? Or even work at all? (My teeth aren't really yellow, but if I could get them just a couple shades brighter I would be happy, so they don't have to be AMAZING, just work a little.)
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I've used Walgreen's brand of white strips and they had the same result: whitened quite nicely and lasted for a while. Don't forget to keep up with your dental hygiene in order to preserve the whitening. I would have to say, though, that the trays/strips each uses are much different. Instead of Crest's clear, thin strip that doesn't stick to your teeth very well, Walgreen's brand has an actual plastic-type of strips that mold to your teeth. They're thick and blue, but they stay on much better and don't make you salivate and taste that weird whitening taste too much. (I usually keep a cup with me so that I can spit out the weird taste instead of swallowing it.) If you want to try strips that are nearly invisible, go with the name brands or brands that say that their strips are clear. If you don't care, I would highly recommend Walgreen's or Fry's brands (I've tried both). You also need to consider the time each takes. Walgreen's (Fry's, too, I think) takes 14 days (once a day for 20 or 30 min) and Crest (and other name brands) offer ones that only take 7 days. In terms of effects on your teeth (like ruining the enamel and such), I'm not sure if there is a significant difference. I haven't noticed any changes in my teeth and I've used all three brands (Walgreen's, Fry's, and Crest) within the past 6 years. I'm thinking about whitening them again, and I'll just go with the cheapest ones that I find. Good luck!
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