There are many makes of shower pump on the market from many sources which makes it dificult for a lay person to know which one to buy. The old adage “you get what you pay for” is certainly true with shower pumps.
A lot of pumps under £200 would be made of plastic and our experience is that these are often the ones we replace because they leak or the motors fail. A good quality pump is made of brass and would cost the best part of £400.
So if you are looking for a good quality shower pump chose a brass pump and expect to pay for it. You will be rewarded for it by the pump having a longer life and some are even servicable with easy to obtain spares.
If I was asked to recommend a good make it would have to be Stuart Turner. So there you have it, some simple good advice. You pay your money and take your choice.