We tended to overvalue much of their tech, but some of it was quite good. An example was the Fulcrum fighter. I can't find the article, but when the USSR fell we got our hands on several. At first, our pilots were unimpressed, it lacked a lot of our modernity. For example, no GPS whatsoever. The pilots had to carry paper maps. Our pilots were pretty hard on it until they tested it in dogfighting against American jets. At lower altitudes, our pilots preferred it to our planes as it was more maneuverable. The Israelis came to the same conclusion. The other huge benefit that we still completely ignore, it turned out that pretty much anyone with a wrench and screwdriver could keep it flying.
I love our equipment but somehow we have failed to learn from the German Tiger tank. It was a wonderful tank, for the 15 minutes it ran before needing servicing. The Tiger had to be started and ran every 2 hours (it was true and strangely accurately depicted in Kelly's Heroes). Alfred Rubble served in Germany's 503 Tiger Battalion and wrote a book on the 503 after the war said in that book that for every hour it ran, it required 10 hours of service. I suspect that is an exaggeration, but even a 1-1 ratio would be very bad.