I have the P85. The only difference between it and the P-89 from what I understand is the internal workings of the safety are different. Ruger recalled all the P-85's within a certain SN range and fixed the guns with a modified safety. Then the used the change and called them the P-89.
On mine, when you depress the safety, the hammer drops and the safety lever stays in the down position You have to manually raise it to be able to fire the pistol.
I know that mine is more accurate than I am.
Paul B.