Universal/Westerbeke Fuel pump: Square vs. Round - which one is more reliable?

[Crow]

I am replacing the fuel pump on my Universal M50. I currently have one of the (newer) square pumps installed. Universal has sent me the (older) round style pumps as a replacement. It is considerably larger. They tell me the pumps are equal in function.

Does anyone have insight into the differences? Is the more massive pump possibly more robust? Is the newer, lighter pump possibly better engineered, with experience of failure modes?

My goal is to have the most reliable pump installed. Thanks for some insight.

[zboss]

I got the same one from for my WB... the round one works fine. In fact, you could potentially use just about any fuel pump of the right size. You could hook a walbro pump inline and that would work just as well.

They are certainly not cheap but I keep one as a spare as well - just in case.