I just got a 300 MM F4 and the 1.4 Longar, and my Aptus II 12R is back from Israel. To those not familiar with this thread, I used a Hy6 with Mod2 upgrade. The day is hazy today but I hope you don't mind the test results are more important than artistic merit.
I did a rough exit pupil alignment on the pano rig, and shot 27 images. You can see the results of the full image, and a 100% crop unsharpened plus a 100% crop sharpened. The big image was not upsampled at all.
The depth of field extended back to about 300 yards, as I focused on the Tower of the Americas. This is the street in front of my studio and I wanted the construction signs in there to help with depth of field observations.
Mirror was locked up, I didn't use a shutter release, and the camera was attached to the pano rig, not the lens (which will be the case very soon). In the studio, I got significant camera shake from the mirror slap, so I had no choice but to lock it up.
These were shot at F8, which is significantly sharper than F11. F11 is still satisfactory, though and the DOF gains may well be worth the sharpness tradeoff.
Thanks to all who helped with this.