Rather well, especially if you consider the fate of its series successors. LEW had a hollow shaft drive type of its own. 4 MW continuous power was somewhat inferior to the best thyristor locos of the time (ÖBB class 1044, 1974: 5.15MW, SBB Re 4/4 IV, 1982: 5.05MW), but not bad. Then again, its electronics weren't an own development... and are rumoured to be in this long lineage:

1. SJ Rc1 made by ASEA of Sweden, one of the very first thyristor-regulated locos (1967)
   
2. SJ Rc2, an improved version (1969)
   
3. ÖBB 1043, an export version for Austria (1971)
   
4. ÖBB 1044 prototype, an improved clone of the 1043 made by Austrian SGP and ELIN, German Siemens and Swiss BBC (1974)
   
5. ČSD ES 499.0 'Gorila' (today ŽSSK 350 in Slovakia), made by Škoda of then CZechoslovakia, allegedly with input from industrial espionage on the Austrian development (1974)
   
6. ČSD ES 499.1 (today ČD and ŽSSK 363), a lighter but updated version (1980)
   
7. DR 212 001 "White Lady": electronics from Škoda (1982)

_{*Lunatic*, n.
One whose delusions are out of fashion.}

Since we tend to assume that everything in East Germany was technologically backward

It depends on which direction you look at it: within the COMECON, the East German products were considered the best quality. (Well, apart from cars...)

_{*Lunatic*, n.
One whose delusions are out of fashion.}