Drefahlaudio capsule reskins will restore full reliability and performance of your microphone in the very first place, especially when elevated noise and closemiking dropouts become a problem. While the factory parameters are the primary goal in most cases, also "matured" vintage capsules with their specific properties can serve as a model.
The plots below are recorded with non-linear music signals, representing real-world recording conditions very well.
U47 longbody with vintage K47 capsule, offering that very desirable "upfront" sound for vocal recording. The custom-reskinned M7 is set to the same acoustic properties and even most sensitive ears won't distinguish it from the model. Now in use as a stereo pair...
Telefunken Ela M250 with original AKG CK12 capsule and a second capsule head with drefahlaudio-reskinned CK12. Also here, not the faintest difference to the valued original will be noticed.
Two Neumann U87 forming a true stereo pair after matched reskinning. After processing, any difference between both is hardly measurable and completely inaudible. For a perfect stereo image !