from my experience, i can say shorter is better on the suction side.

on the pressure side the lenght is not anymore a problem.

in my Eurosport the pump and UAT are beetwen the tank( in front of the turbine), but on the pressure side i go with the tube on the front of the model (under the canopy), where i have a manual valve and the solenoid valve, and back to the turbine..a good meter of tube...

just the first time, the turbine will run longher on gas, or not ramp on fuel, when tube are empty..