Replacement Hymer external water pump.

Tirril

I have a 2017 Hymer Nova caravan which uses a Comet VIP Plus 12 volt external water pump. Two have failed and I am considering buying a different brand. Although small in size to allow it to  immerse into an Aqua Roll, the Comet claims to pump 20 litres a  minute at 1.1 bar. The alternatives such as Whale seem to be less powerful. I would appreciate any advice on a suitable external pump and whether anyone has suffered a short life span with the Comet or have I been unlucky?