There's a lot of ROTS that's not common on the pegs, and there's quite a bit that never was. Some of it was here in abundance at one point but the line just sold so well it moved fast.
A lot of the 4/2 release items sat for the longest time... Things like Chewbacca, Tarfful, Col. 2 Jedi, Col. 1 characters like Obi/Ani/Yoda... Then the film came and those are all but gone. I saw a brief resurgence of Chewie but he's gone now too (I'm holding one for a guy I know wants it for his son).
Figures like Mustafar Duel Ani/Obi have sold well and I haven't seen either now for a while. the other Ani and Obi sold somewhat ok, though Obi (the kicking one) is fairly common here now. Anakin still moves.
Pittsburgh is, as far as I know now, literally out of Lava Anakins. A buddy got me the last one at his Target, thankfully, because I waited on those but then all of a sudden Anakin sold out... Obi's are usually 2 or 3 at a store and that's it. I never would have thought those would have moved.
Clone Commanders come and go... All 3 paintjobs sell out, and I can't say they've sat at all. I'm surprised considering how often I'd seen them at stores over the last 2 months or so, but then these same stores I'd visit a week later, or even just a couple days, and what I saw wasn't there any longer.
Clones (#6) are non-existant... I never saw a Shocktrooper on pegs, not once, and that pisses me off. I'd have built a hefty army but instead I'm settling for a squad. Black Pilots barely surfaced here as well however I did find one here, or one there... Never more than one though at any point.
SA Clones are also drying up around here as I figured they would. Heavy shipping over the last few months filled the pegs but now I see at most 6, usually less though, at any given store. AT-RT Drivers and Clone Pilots are the same, and are becoming more scarce.
Any of the final 12 are scarce, though I'd say Wookiee Commando and Gree are semi-easier to find. I see them regularly, but not in abundance. Just a random couple hanging around here and there. All the others though are pretty much a pain to find anywhere, and of course the Wookiee Gunner, 501st, and Holo figures are the biggest pains to find out of any of them.
Short of TRU I don't see the Collection 2 Jedi much at all... Agen Kolar, Ki-Adi Mundi, and Plo Koon have become 3 fairly hot figures actually. Tack onto that C-3PO, Count Dooku, and Padme as well which I haven't seen any of those save for a 3PO that surfaced at KM during Black Friday.
In Pittsburgh the Polis Massaan and Med Droid were never all that common either.
The pegwarmers here are the usual suspects once again it seems, with Palpatines, Bail's, Neimoidians and the like being easy to find...
ROTS has been such a weird line though where one week something's impossible to find, next week it's not, then a week after that it's impossible to find again. There's some stuff that's definitely been a pain for the majority around the country though, like the Shocktroopers, "final 5", and such... The rest seems to be very regional as to what was hard to find and what wasn't.