Compared to a turbine (westco) pump like the Bosch 044 this pump design will inevitably produce more small pressure fluctuations due to the positive displacement design. It also has a few more failure points with the fiberglass diaphragm and pressure relief valve and integrated check valve.
The motor is a brushed motor, which means it has a finite lifetime and inevitably will wear out. The gear rotor has metal/metal contact and will also probably wear out (or seize). The electric motor has no ball bearings -- it is held upright by raw plastic/metal contacting "pegs".
Here's the patent on the westco pump:
http://www.freepatentsonline.com/3233551.pdf
It is my understanding that the Bosch pumps use this basic design but packaged in a more appropriate way for a fuel tank. Reading the more recent NipponDenso patents and Bosch patents it seems only very minor improvements have been made from the 1966 design. (Mostly regarding pump channel and the water wheel aerodynamics)