The EZ 42 was compared with the Allied G.G.S. captured from in a P-47 Thunderbolt in September 1944 in Germany. Both sights were tested in the same Fw 190, and by the same pilot. The conclusion was critical of the moving graticule of the G.G.S., which could be obscured by the target. Compared to the EZ 42, the Allied sight's prediction angle was found on average to be 20% less accurate, and vary by 1% per degree. Tracking accuracy with the G.G.S. measured as the mean error of the best 50% of pictures was 20% worse than with the EZ 42.