We use the plain Addis baby bath seat as it holds the baby very nicely.
Friends of ours with a 3 month old came to visit some weeks back and borrowed ours and they told me that the Addis works better than their Angelcare because they are not "held" by the Angelcare.
Since I don't have experience with the Angelcare I'm sharing theirs In my opinion, the Addis one works wonderfully.