I disagree.... The gun and armored bathtub were very good.... The rest of the aircraft, and especially the engines, were crap...... It could kill tanks, sure, but a large percentage of 129's that were lost, were operational losses...
Those Goddamn Sucky-Ass French Gnome-Rhone 14M radial engines.. GRRRRRRRR.... Ruined a possible great anti-tank aircraft.........
By late 1942 complaints started about the MK103 (on the 129B-2) against newer versions of T-34.... For some reason the Luftwaffe skipped the 37mm cannon, and installed the big ass 75 mm gun from the Panzer IV, and created the HS-129B-3....
A huge hydraulic system was used to damp the recoil of the gun... The resulting system was able to knock out any tank in the world, but the weight slowed the already poor performance of the plane to barely flyable in this new Hs 129B-3 version......
B-3's only started arriving in June 1944, and only 25 were delivered by the time the lines were shut down.... A small number were also converted from older B-2 models..... Over the lines in Russia, they proved deadly weapons, but with only 25 of them they had no REAL effect on the war effort.....