Whale Pump Instead of Truma Crystal Pump?

I have a caravan which has a Truma Crystal submersible water pump.

I want to buy a new pump and was wondering if I have to get a Truma one or can I get a Whale one as a few people have recommended this brand of pump.

The connection looks the same but I wasn't sure if there is another reason that I would have to have the Truma one.