Another unit who received Bf-109G's was the 52nd Fighter Squadron, who was stationed inside Romania on Mizil airfield, close to the oilfields of Ploiesti. After training on He-112 and Bf-109E's they switched to 'Gustavs' in early March 1943 and formed a fighter group together with three German squadrons. During operation "Tidal Wave", the squadron shot down two confirmed B-24's ( one was downed by adjutant Mitrica Encioiu and one by second lieutenant Ion Maga ).

By the summer of 1944, two fighter groups ( the 7th and the 9th ) had been equipped with Bf-109G's. After serving with distinction on the east front, the groups were recalled home to fight against the bombing raids of the 15th USAF. Throughout the summer of 1944, the Romanian 'Gustavs' clashed with the B-24's, B-17's, P-38 Lightnings and P-51 Mustangs of the 15th USAF. Although they fought heroically and scored a lot of kills, the sheer weight of numbers was too much, and by late August both groups had been decimated and exhausted.

After the 23rd of August 1944, the remaining Bf-109G's were used to create a mixed unit ( initially referred to as the 7/9th Fighter Group, but was named the 9th Fighter Group in the end ) who fought until the end of the war. They clashed with German and Hungarian Bf-109G's and K's a few times, and adjutant Traian Darjan and adjutant Constatin Nicoara managed to shoot down a Bf-109K each on the 25th of February 1945. It seems that those were the last victories achieved by ARR's fighters in World War Two. Another fighter group, the 1st, arrived on the front in February 1945, after it had been re-equipped with Bf-109G6's. The 6th Fighter Group also received 'Gustavs' instead of its IAR-80's, but it remained home. The Bf-109G's remained in frontline service right until the last day of the war, by which time they had established themselves as the finest fighter in ARR service. Most of the Romanian aces flew the 'Gustav' and got most of their kills whilst flying it, including the top three aces : captain Constantin Cantacuzino ( 56 kills ), captain Alexandru Serbanescu ( 45 kills ) and adjutant Ion Milu ( 45 kills ).

The Germans agreed, but production could start only in mid 1944, when Romania was being attacked by the bombers of the 15th USAF. One raid hit the IAR factory, causing heavy damages, so it seems that only a handful of Bf-109G6's ( some sources claim that only six while others say 20 ) were produced and handed over to the fighter squadrons. After Romania left the Axis, production wasn't disrupted by bombing raids any more, but it faced other problems, as some of the components previously shipped from Germany ( armament in particular ) weren't coming any more, so the engineers had to make do with what they had. Nevertheless, production continued for a while after the war, by which time it seems that as many as 75 'Gustavs' were manufactured.

At every one of these one can give pluses and minuses to any type, and the immediate way of giving a verdict would be a simple addition. But none of these characteristics is essential. Other elements appear : when I entered the G's cockpit it was like putting on a glove. Everything fits. Everything was right in place. Everything was well thought of and placed handy... It wasn't the Lightning or the Mustang as type that beat us ; they could never have done it ! The Mustang and the Lightning beat us in numbers and maybe in tactics. "