A couple of weeks ago I bought 80 Finish Powerball 0% dishwasher tablets. After I used the first one the contents of the dishwasher, the door and compartment were covered in a white powder residue that took two washes to get rid of. I rang the phone number on the bag and had a chat with a lady who said that should not have happened and that this was probably a one off. I took her word for it and tried again and exactly the same thing happened and I had to do another two washes without a tablet to get everything clean. I phoned again and was told they would look into it and send me some vouchers, I didn't receive any vouchers or a letter informing me of the outcome of their investigation.
This was all rather annoying as doing six washes instead of two certainly did not help the environment or my electric and water bill! and the tablets were quite expensive.
I have gone back to Ecover tablets which I have always found to be as good as any.