When I was doing Duncraig for leveling I would find a notable SU every 4-5 runs. Rogue foresight has dropped for me twice there. (once on my way in, and once in Duncraig proper).
Having said that, your best bet is to progress onto Bremmtown. I'm sitting at 350 mf, lvl 140 (it matters), and I get a SSU or SSSU once every 5 or so runs, 0-2 SU's per run. That doesn't even take into consideration the jewelry, shrines or runes I get on my way to Bremmtown. For me personally the item drops (I.E. armor and weapons) have been terrible in Fauztnville proper.
Edit: I'm a barbarian w/ 1.1mil defense and 50% phys res, so Bremmtown is really good for me. There are a lot of classes//builds that will struggle though.