Great information. Thanks for sharing.
Since you have a lot of experience with the P89 and the 92D how does the P89 DA pull compare to the Beretta? I've got 4 Beretta's, 92g, 92FS, 92FS Centurion and PX4. All of those have smooth DA pulls, especially if the sear has been removed. If the Ruger is close to that I'd be tempted to give one a go.