Regular push-in Festo style fittings can display a problem that could cost you an airplane.

The bend radius needs to be large enough to prevent the fitting from sucking air. Bend the line in too tight a radius, and the tubing on the outside of the bend will migrate away from the conical seal, and you will get an air leak. One big air bubble too large for the pump to process, and you have a flame-out.
Proper routing of the lines will prevent this. It is not a sin to have large bend radii in your fuel system.

Conversely, barbed fittings, like supplied on the BVM UAT, won't leak at small bend radiuses.
I've been there, and done that.

A word to the wise...........