I think you're leaving out the biggest benefits of the Sub-C over the Dweller. As Bo said, it's all about the bracelet. Solid center-links, "glidelock" clasp for precision micro-adjustments, milled clasp. The Sub-C bracelet is probably the biggest single upgrade you're getting between the 16600 and 116610.
Another big one is that Sub-C has the cyclops, but before writing it off completely, check it out in person. The AR coating behind the cyclops makes it LOADS more useful than the standard one on the prolific Sub-Date.
The differences, in a nutshell:
- bracelet
- cyclops
- maxi hands/dial/case
- thickness
- HEV
- lume
- bezel
- movement (slightly)
Price-wise, you're talking about a watch that's a FEW thousand dollars. Don't think about the price yet. Think about which one you really want, price aside. THEN set out finding the best price (you can probably do better than $7400 on a BNIB Sub-C, I'm thinking). Used prices for the Sub-C from private sellers go down as low as $6500. And used Dwellers as low as $4800ish.
So decide what you want first - then we'll talk pricing.
