Shortround6
Major General
in the cost-benefit analysis we need to count that somewhere you can have a 110 but not a 109, or you can have a 109 for X minutes or a 110 for Y minutes, you can attack/photograph that installations with a 110 but not with a 109, or the same installation with more weapon load. it is out of doubt that a two engine aircraft is more expansive to build and use in comparison with a single engine, if the engine are the same
This starts to get into the light fighter vs heavy fighter argument.
The 110 (in 1940) carries twice the machine gun ammo and 3 times the cannon ammo of a 109 into the combat area. Since both planes carried a ridiculous amount of machine gun ammo (nearly a minutes worth) that may need some compromise. Few 110s may have gotten to their 3rd set of drums of cannon ammo but a number might have made it to the 2nd set of drums.
How valuable was the ability of the 110s to talk to the bombers by radio?
How valuable was the ability of the 110 to communicate with their bases or listening stations much further away than a 109 could could?
The 110 had more operational radius than a 109 if neither had drop tanks, touched on by Vincenzo along with the fact that for fighter bomber duties (also mentioned by Vincenzo) one 110 equaled two 109s in bomb load.
The Germans were getting extra capabilities for the extra cost, question is if was enough, but it any case it wasn't a pure 2 to 1 ratio in favor of the 109.