I have been using contacts and just got the zeiss lenses today. So far it's roughly equivalent. I think there is a touch more distortion (chromatic aberration along the edges) with the inserts. But my contacts are progressives and kinda sucked for this, single vision would probably be great.

The purchase path in the online store will ask what kind of contacts you have, and if they're compatible will recommend using them instead of inserts.

The main advantage is that it's less crowded in there, I suppose.