Without getting too deep into the armour values of Soviet tanks, I can assure you the R4/M and 30mm could destroy anything the Soviets had. The Soviet Armour even from the ground was extremely vunerable to the Panzerfaust, as they found out in Berlin.
The R4/M actually paved way for the Mighty Mouse FFAR folding-fin aircraft rocket. Even more scary was the X-4 a wire guided air-to-air missile with a range of 2.2 miles. They tested it on Fw-190s and they were about to test it on Me-262s but the war ended, it never got used in action but it would have been deadly if it did.