[BikerJoe]

Amazing what he did with the crappy metallurgy of the time.

Yes, but Whittle's design didn't have as high a metallurgical demand, and had a lower power/weight ratio, I believe.

The Germans had the first "modern" jet engines, and they lasted (at the outside) 25 hours.

Whittle's engine would run forever, though.

[Fred Hayek]

Whittle’s jet and the Jumo 004 were two different approaches. Whittle’s engine was a centrifugal turbojet, which was mechanically simpler, but in the long term limited.
The German Junker Jumo 004 was an axial flow turbojet. Being lighter, it also required higher metallurgy for the turbine blades. Throw in tighter tolerances.