A spare pump in case of failure is a useful thing to have if you intend keeping the boat for more than a few years. These jabsco pumps have quick connections, so it's usualy only a 15 min job to swap over.
As a general installation point, as said above, flexible pipe is preffered for the final connection to a pump. Both at its inlet and outlet. Installing the pump on a vertical surface with the pump head lower than the motor, and a receptacle of some sort (we use a lunch box) to catch any drips, when it does inevitably start leaking, will hopefully prevent your wood work, and the bilges being damaged in the future. Some people even put a water leak alarm beneath to give an audible warning. You have to give some thought to damping the vibration caused by the pump on a hard surface too, and the noise it produces. Whilst these pumps generally have rubber feet, that do an ok job, its not always enough.
Having said that,you don' t want a pump to be totally silent either imo, as its a good indication of when a leak does begin, but only if it is on the high pressure side of the pump.