Selecting the ideal water pick up & outlet has required some good thought and been based on much trial & error experience. I have found that most all metals seem to suffer from a large degree of surface corosion and a salt/calcification build up, which can quickly clog up the intakes. Plastic is very suitable for a salt water enviroment and eliminates the salty/calsification build up. The size of the inlet oriface also aids in the restriction of bigger pieces of debri's entering into the system, otherwise, either then getting stuck in the esc's water cooling jacket - or- the motors water cooling jacket, which can be hard to unblock / clean out, especially when on the beach. Genrally, rc Surfers are not operated under full throttle for lengthy periods of time, so maximum cooling is not a priority. I have run this system since testing the very first Production, board with good results - and - not even a breakage to date. It is a very effective, yet a very avaiable and inexpensive component, which serves the system well overall.