Messerschmitt Me.410 - Foreign Users

The Messerschmitt Me.410 (nicknamed "Hornisse" - Hornet) was a German heavy-fighter and fast bomber that was used by the Luftwaffe during the World War II. Although it was basically an improvement of the previous Me.210, it had a completely redesigned wing, longer fuselage and more powerful engines. As the changes were significant enough, it received the designation of Me.410.
It was used by some foreign countries, though the type wasn't exported.

• United Kingdom: There were at least three Me.410 captured by the United Kingdom. One of them was captured at the town of Gerbini, in Sicily, by the British. It was test flown by the No.601 Squadron and then handed over to the American 12th Bomber Group, but it crashed in October 1943 killing the pilot.
  Another one was taken by British Troops in May 1945 that had previously served with the ZG.26. The aircraft and its crew surrendered to British troops at the town of Vaerlose, in Denmark, in May 1945 and became one of the six that were sent to the United Kingdom for evaluation. It was repainted in test colours and assigned to the No. 1426 (Enemy Aircraft) Flight, RAF, the famous "Rafwaffe". It was selected for preservation and is nowadays shown in RAF Cosford.
  
• USSR: After the German retreat, the Soviets captured loads of German material. Among them there were some Me.410B-2/U4 which were distinguishable by the anti-tank cannon at the nose. At least one of them was captured intact and in flying conditions in Poznan in October 1944. It was sent to the USSR ,assigned to the NII-VVS (the aeronautical research section of the Soviet Air Force) and flown by test pilot Maj. Ivan P. Piskunov who was later promoted to Lt. Col. and had the title of Hero of the Soviet Union. It was tested until 1946 and was discarded shortly after.

Sources:

1. https://en.wikipedia.org/wiki/Messerschmitt_Me_410

2. https://en.wikipedia.org/wiki/No._1426_Flight_RAF

3. Salamander Books - The Complete Book of Fighters