I knew a WWII M3 tank crewman whose saddest day was when his M3 light tank was replaced with an M5 for the invasion of Sicily. Until he found out the M5 had a gyro-stabilized gun, and could shoot on the move, sometimes a necessity for the crews in the light *Cavalry* tanks going up against enemy vehicles with bigger, but not necessarily better, guns, often at night when long-distance range didn't count for much.
Finishing the war as a driver, he missed shooting at people, and so had a 2.36-inch bazooka wired to the tank's barrel, fired by means of his horn button. He said it was great at night, but the backblast necessitated an immediate relocation at night- the flash gave away your position instantly.
Good anecdote - American ingenuity. :-)