So I have been wanting to get my teeth whitened for a while now (black coffee grr), not just because of the wedding though that is what has given me a kick in the bum to get going with it! I spoke to my dentist who said £500 and something for laser "in-chair" treatment, or £295 for moulded trays and the "liquid" that goes in them, to wear every night for 2 weeks. The trays are then reusable and the "liquid" can be purchased for later use.
I have been on groupon and there are loads on there that sound a bit dodgy, but there are 2 or 3 clinics in London which describe the exact same at home process as my dentist has described. These are £90-150.
Has anyone done this? Do you think the groupon offers are essentially the same thing as what my dentist is offering? Obviously there are some that are £20-30 which I expect are a waste of money, but as these are exactly as my dentist described and are still a decent amount of money to pay, my impression is that they are probably legit. They have good reviews averaging 4*.