The Westerns were kind enough to be most of the way to breeding plumage, complete with the arrow chevrons going down their flanks.
Here's a different individual.
Western Sandpipers of Oct 2013 and of Sept 2012 had longer bills.
This one was still in winter plumage.
I can't tell if it's just the angle making the bill look less tapered and drooped or if this is actually a semi-palmated.
Leasts on the other hand certainly had thin tapered bills.
I think my memory of Western Sandpiper gets influenced by the much heavier curved bills of Dunlins as well.
Most of the dunlins weren't even this far along in their moult and I didn't take a ton of pics of them.