Oakley clear lenses are quite expensive and the anti reflective coating is your only option. No anti scratch or dirt repellant coatings? You're also restricted to polycarbonate with an index of 1,6. Where Oakley does shine is with highly curved (base 8) lenses. I've never experienced optical distorsion with Oakley lenses but I have with other manufactures. Though Zeiss now also has adressed this issue with Claret loop.
So while I think Oakley has the market cornered for prescription sunglasses your options for clear prescription lenses are far more extensive.

I cannot say enough how awesome these lenses are for me. One thing I hate about wear Rx is that you can see your eye or reflection in the lens. It always bugs me b/c I feel like they are dirty but they are just the reflection. I got these in my A wires and they were so awesome. So clear and crisp and I didn't have the light reflecting off either so I could even take pictures with them on.