WayneS has a good point. Its probably like trading you old car for a new one at a dealership? Your always going to get more if you sell it outright,then apply the money towards the new purchase. Plus, selling a barrel here is a whole lot easier then selling a car, lot less tire kickers and less phone calls from folks just wanting to talk about their cars they had in the past.
While a 357 mag,10 inch might not be a hot seller here, you will find someone willing to buy it.
I have one, I like it !