Canister filters – Aquael, Eheim or Fluval

Icemist Member Posts: 10
I am after some recommendations of Canister filters. I want to over filter the tank.
I have a 250 litre tank running a few discus.
I am looking at a new filter and was considering:
Aquael Unimax 500;
Fluval 306 or 406; or
Eheim Classic 2217 (600).
Especially interested in comments on the Unimax 500.
Thanks in advance