This was bought to replace one that we used for 13 years with no problems.
The item does not work in the same way, the pump does not kick in straight away like the old one did, we have to turn the temperature of the water down to cold and then keep turning on the tap until the pump decides to kick in and then slowly increase the temperature. Not ideal
the main reason is the speed control of water flow you can control it to suit your flow ive recently bought 8 for a hotel where they had the old low pressure flow I could adjust flow from 1 to 3 to suit the rooms
When purchasing looked for similar size and shape to previous so avoiding need to alter pipework. This one fitted the bill. Straight forward DIY replacement. Requires 3 core cable and connection. Much quieter than previous 12 year old pump. Powerful enough for our needs. Appears well made but after only two weeks use probably too early comment.