factory fitted on all spits from the summer of 1944.
The RAE was still gleaning data from gun camera films on GM2 equipped Spitfires of all Marques as late as May 1945. I would be surprised if all Spitfires came equipped with a CGS sight. In fact, that would be a bad move according to the factual data amassed by the RAE.
A training program was enacted by the RAF in the last six months of the war to bring the CGS lethality up and over the fixed projector sights lethality.
The GM2 reflex site was just proving itself to be more lethal in combat.
The British CGS sight beat out the GM2 reflex sight in lethality by a meager 3% over the same time period by the end of the war.
The technology was just very new, far from perfected, required some experience, and training to use effectively in combat.
The Germans also produced and fielded several hundred examples of the EZ42. It was commonly used in the Me-262, FW190A8/9, FW-190D9, and Bf-109 series.
Between the British and German CGS sights, it depends on who you ask as to which sight was better.
The British describe the EZ42 as the most modern sight in the world. The German experience relates it improved accuracy almost 2:1 over the fixed reflex sight including accurate shots at ranges over 400M and 15 degrees deflection, the sighting limits of a fixed reflex sight. However they acknowledge that its effective use takes considerable training especially in fighter to fighter combat. The German data was gathered in the form of operational trials and subjective experience reports. The British did not feel this methodology yielded sufficiently accurate scientific data.
The Germans felt the British CGS margin of error was too large with temperature and altitude variations. The British felt the German testing was not an accurate reflection of their system.
The USAAF devoted more hours to training and averaged almost twice the flying experience in its pilots over the RAF. This is reflected in their experience with CGS sights.
The British and Germans found their was little practical difference in lethality between CGS sights and fixed reflex sights. Once again, a reflection of the aircrew training programs.
All the best,
Crumpp