By "five shot rule" he means putting the hammer down on an empty chamber. Right now that's the only safe way to carry it.
Hrm.
Look, my understanding is that the transfer bar safety conversion doesn't screw up the trigger feel that badly. And if you have kids around (or any kids you want to teach handgun shooting) the Bearcat WITH a safety is pretty much the ultimate. They can't accidentally crank off another round DA without cocking it...it's sort of equivelent to the gun going "on safe" after every shot.
Without the safety, it's best served as an adult's gun only.
The safety conversion requires swapping base pins...the transfer bar base pin has a spring-loaded plunger on the rear to push the transfer bar backwards so it passes over the firing pin on the way up. That's how all the other transfer bar Ruger SAs work so I suspect the Bearcat is similar. If so, the only base pins you're going to find nowadays are going to be the revised action type. And Belt Mountain isn't making Bearcat pins...well...it's not on their website, maybe you can call them and confirm:
http://www.beltmountain.com/ruger.htm
Huh...on the site it says Bearcat pins are "coming soon", and since they're very slow updating their site...yeah, definitely give them a call. They're the top source for Ruger base pins. If his have the plunger, MAYBE you can cut that off and use it in an unconverted gun, or maybe BM will sell them both ways.
Putting a REAL base pin in might correct the accuracy issues, or it might not.