The price is marked down because this is an older line. The new line is SE210, SE310, SE420, SE530. That said, E3c is a great piece IMHO, and competitive at it's slightly marked down price.
Important: See if you can order a set of the Shure "Black Foam" ear piece inserts. These are generally considered to be HUGELY better than either the rubber or yellow foam tips that come with your unit. Seriously, if you are like most people, you'll find the "black foamies" a revelation. I did. They seem to combine the best features of the other tips. They are WAY more comfortable than the other tips, and yet provide excellent isolation. Isolation is necessary for achieving good bass response on the E3c.
You can find them at www.earphonesolutions.com or www.shure.com.
ps: Excellent with nano. Head amp is not necessary, although it would be nice. Adding an amp can be a tradeoff, as you get more power, dynamics and bass control, but probably a little less transparency.