>In addition, the GE FDL used a jumper line between injector pump and the actual injector nozzle that was subject to splitting under high pressure - and right near the exhaust manifold.

Cooper-Bessemer (GE) and MacIntosh & Seymore (Alco) use what is called a "Bosch jerk-pump" injection scheme, in which a cam driven pump on the side of the cylinder housing makes the high pressure. The high pressure line will fatigue at just the wrong point: where it will spray finely atomized fuel on the exhaust manifold, where it catches on fire.

>EMD used a unit injector so did not have the same issue.

The plunger inside the injector, also cam driven, is what makes the high pressure.

With both types of enigines, there are external (low pressure) fuel lines.

>I have heard that GE uses a high pressure fuel line to supply the EFI injectors on the newer designs. I'm not familiar with the newer engines - I like the older and simpler designs.

The only big difference between EFI and governors with both types of engine is that the injector is turned on and off by the computer, not the layshaft (unless you want to dicsuss RPM detection, which is also quite different, and engine protective devices, which are not).