While I would never bash a purchase of a Security Six
Dude, you got a 6" barrel for CC?
Que?
Anyways, you got an excellent handgun, and one that will last forever if maintained. I think, however, you may have made a mistake selling the Glock for the Ruger if your intended purpose is CC.
(God, please don't strike me down for suggesting someone keep a Glock over a Sec Six).
As for value, I have been seeing Security Six's in my area go for anywhere from $400-$600, depending on condition. They have become popular again, and are bringing in a premium.