I didn't buy this through Amazon but from a local pet shop, and to be fair to the fellow there, he doesn't really deal in aquarium supplies but found this via his rep.
I've had it 3 weeks - Don't buy it. It is so noisy and it leaks. I turned it off one evening while watching tv as the thing was making so much noise, and an hour later noticed the water level in the tank had dropped. discovered 4 litres of water all over the floor(I know because that's how much I needed to top the tank back up). it was dripping water from the where the lid attaches down to where the power lead goes into the unit.
I've taken video to show leak and the noise and am going back to the shop for a refund. I was offered a replacement but have no faith in it. Should have bought the one for 20 quid more that I had originally, which worked perfectly until I broke it.
Seriously, spend a little extra and get something decent.