What do you guys think a Knight Disc Extreme .50 cal SS/Laminate is worth? The gun is 3 or 4 years old, it has no corrosion or scratches. It comes with an additional composite thumbhole stock and a weaver 4x-10x scope with weaver bases. The guy says he will sell it to me for $315.

I was set on an Omega, but this sounds like a heck of a deal to me, however I have no idea what used BP guns go for.

Any help would be appreciated.