Fuel flow meters have its field of application where can be called as best solution.
See this article.

On what to pay attention when choosing a fuel flow meter:

1. Correctly choose the type of flowmeter (single-chamber or differential). In order to reduce the cost, customers are often offered single-chamber flowmeters, the installation of which requires a change in the fuel supply scheme and a change in the operating conditions of the engine. Contact our technical support for assistance in choosing.
2. To work accurately on idling differential flowmeters should have fuel temperature sensors in each of the chambers. In the “supply” and “return” lines, a significant amount of fuel is constantly pumped. Since they have different temperatures, the created measurement error can substantially exceed the fuel consumption at idle.
All Eurosens Delta differential flowmeters have built-in thermal sensors in each of the measuring chambers.
3. Pay attention to the warranty conditions mentioned in the passport. Some manufacturers limit the normal warranty period by fuel amount passed through the flowmeter. In real operation, this period is over after 6-12 months.
Eurosens Direct and Delta flowmeters are accompanied by a 3 years’ warranty without fuel flow limitation.
4. Try to choose flowmeters with a Hall sensors instead of reed switches. Reed switch can be be brought into non-operational state by applying an external magnetic field. All Eurosens flowmeters (except for autonomous ones) – PH, PN, RS, CAN series use Hall sensors in the design.