After the Sept 44 combat trials of 30 la7, 462 sortie in 30 days. Below are the numbers for the rest of the war.
The 156th Fighter Air Corps of the 4th Air Army was the next unit to receive the La-7 in October 1944. At one point during the month, they had fourteen aircraft simultaneously unserviceable with engine failures.[7] By 1 January 1945 there were 398 La-7s in front-line service of which 107 were unserviceable.[9] By 9 May 1945 this had increased to 967 aircraft, of which only 169 were unserviceable.[10] For the invasion of Japanese Manchuria, 313 La-7s were assigned and only 28 of these were unserviceable on 9 August 1945.[11]
Because of the superior performance of the La7, on the western front, the 1000 or so that were ever able to fly in combat, were heavily flown to engage the Germans at a time everything was heavily flown by the Russians to destroy Germany. There was never numbers like the La5 available for combat.
Consider that from 1941-45, 2591 La5 of all types were lost in combat versus the 1365 La7 available that were assigned to combat against Germany then Japan. Around 9000 La5 were produced. I would give the title of heavily used to the La5.