I got the Navman Twin Engine 3100F fuel flow meter (AA02625R). and another transducer kit (AA002284R)...to monitor 2 engines. The Navman seemed to display more parameters than others I looked at, and was definitly cheaper than models from Floscan and others.
I guess that's it, I was originally using a carbuerated engine manual to check out the fuel system, and it stated in bold print, not to add anything like an extra fuel filter, because of the possibility of increasing the fuel line back pressure....which they stated would be a no-no (lean condition). I just got my MPI manual, and could'nt find any such warnings. So I assume it won't be a problem.