Ben Pearson bows are definitely under rated. The Mace, however was part of the "Golden Sovereign" line of Pearson bows. These bows were better quality than the standard Ben Pearson's, and also better than the Locksley line which was another line of Pearson's. They did this for marketing reasons.
Although the Sovereigns were somewhat based on the basic Pearson bows, they usually had a better quality of wood in the risers and were more aesthetically pleasing.
I don't know which Pearson design the Mace was based on, but it should be a good solid shooter if it is in good shape.
Good find.