From what I have read, ebony is about one of the best wearing natural handle materials out there. I would think, over time, the jigging on the bone would wear noticeably more than the ebony. I have both, in two-bladed version, and they're both really nice.
One advantage of the single blade, I guess, is that it might be a little easier to open the blade. Being GEC knives, they definitely have strong springs. Not nailbreakers, but firm. Without the pen blade in front of it, I suppose you would have more room to get your thumbnail in the main blade's pull. However, that being said, I don't have any problem opening the two-blade version. There is enough space between the blades to get your nail in there just fine. Personally, I think the pen blade is more advantageous than the possibly easier access to the pull on a single-blade version.
Overall, I have become a big fan of these knives since I got them. Let me know if I can answer any other questions or would like pics.
Edit to add: Hello to a fellow Pennsylvanian!