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I have this lens and I use it with a .85 body. I was worried when I bought it that I would not use it much, but I have and the results are terrific. I have also (at f11) used it on my Konica Hexar (0.62), but with frame lines the size of your thumbnail, it is not ideal.
I seriously doubt if you could tell the difference in the images created by each lens. If all your pictures, taken with your 135MM lens, are taken at F4, then the APO would be somewhat sharper. Once past F4, however, the differences "might" be noticed in enlargements greater than 16X20.