Lie Nielsen sends out a news letter on a regular basis.

This month there was a comment about their new O1 bevel chisels.

Our A-2 Steel chisels will hold an edge extremely well, especially when sharpened at an angle of 30 degrees or higher. Some folks however prefer O-1 Tool Steel, because O-1 holds up better at lower angles, 25 degrees or less, making them more useful for slicing or paring tasks. So in response to customer requests, we are making our standard five sizes available in O-1.
jim