I have a fair collection of Sakos, all purchased while stationed in Germany in the mid-late sixties. In my opinion, Sako is if not the best, one of the best production made rifles ever made. Although I have guns in many calibers, the .243 is my deer hunting gun for Texas whitetails. Since it has the heavy barrel, it is not a gun you would want to haul around if doing a lot of walking, but for hunting from a stand, it is perfect. A real tack driver, I have killed many deer with this gun.
AS for the trigger, most Sakos I have experience with are smooth out of the box, they are adjustable, and can also be lapped to make it even smoother. Advice, if you don't know what you are doing don't try to lap it yourself.
As I said, you now have one of the finer guns made, take care of her and she will make a great piece to hand down to you son.