I have found that if I keep my bucket as flat as I can while still getting the job done, "rollover" is reduced. Keeping the bucket and edge flat will also lengthen the cutting edge's life because you are spreading the wear over a greater surface area.
In contrast, the more you angle the cutting edge perpendicular to your work, the greater the chance of the cutting edge of curling back at the edge. I have found this to be especially true on pavement.
I agree with the other posters by saying that you should just use the bucket and then have a new edge welded on.