Most of the dealers around here won't take a 40 in trade, they just can't move them. That's why it's $357. If you want a 40, it's a good deal, probably a very good deal. But the used 40 market is all but dead.
I keep buying 40s for this reason. These days I can buy .40 ammo for a small fraction more than 9mm anyway. The guns are basically being given away and who knows, in 15yrs the .40 will probably be the trend again - and if not I got some deals on guns I enjoy.