Friend John:
I claim no expertise on the matter, as you well know, but I would go with the Fox. That's a gut call, but based primarily that you have to find less of an "afficionado" to sell the Fox, whereas the Sterlingworth, as stated, is rarer, there is also a lesser realm of potential purchasers.
On the other hand, I'm an Ithaca guy, and could be absolutely totally wrong - But I dont think so.
Great to see you post again. It has been a long time. The world does indeed need more Extraordinary Gentlemen, and I hope you are mentoring a few.
Regards
GKT