You will get hosed trading it in at a gun shop.
Better to sell it outright, night guards are somewhat sought after.
Put it in the classifieds and ask $700, should go for that.
I never liked the adj. sights on my 2.5in 686 for carry, too much of a chane to snag a shirt, or break a rear sight blade.
I like the sights on the NG much better,snag free and tritium.
I love the moonclip reload, but the sights alone give the nod to the NG for carry.
For defense against two legged creatures I load a Barnes 225grn XPB and 20grns of VVn110.
For plinking I use Xtremes 240grn fp and 10 grns of Universal.
Both are easy on the hands while still delivering magnum-like performance.
The fireball out of my Alaskan gets alot of attention at the range:)