I own a Cooke XVa. It is formulated for modern film types.
If you are shooting film from Ansel Adams era, then the XV will do you fine.
What can I say other then it is a marvelous lens.
Some of these images in my gallery were shot with the XVa, but right now I can't remember which ones. I don't write this stuff down. Anyway, these little internet jpags can't show you the incredible image quality the XVa produces.
Of course how you shoot might not work with the XVa. Everyone has different expectations. I find it a very versatile lens for what I do, plus saving weight in the camera bag.