I need an opinion on a Beretta 92B Brigadier Border Marshall 9mm I have put on layaway. It is in good conditions, some holster wear which doesn't bother me, minor shooting, even wear on the slides. $549 with 2 10rds mags and box, night sights with some life left in them but definitively not new. Found the DA pull stiff, SA is OK a bit on the slow side (thinking IDPA). Should be able to fix with lots of dryfiring I noticed that the sights are dovetailed and removable. Are there fiber optics sights can be used on this gun? Night sights to replace the existing one? Is it OK to post the serial #? If yes I will, to ascertain when it was manufactured. Opinions?