Now aren't all lenses, of theres, cut from a blank?Different base curves, different blanks. Rx may be an entirely different story. If your optometrist does it (or more likely the lab they send them to), obviously it isn't Oakley's lens anymore. Even if Oakley would do it as a plano, it would be the full Rx lens cost about $200.
M frame lenses have a z axis curve like Mars do.What do you mean by Z-axis curve? Most Oakley lenses are wrapped, raked, and are taper corrected. I don't see what makes M-Frame lenses particularly suitable besides their size.