I believe the IO540 Grumman STC is for the Tiger, the conversion is called the 'Sabre-Toothed Tiger', FWIW. Includes 3 blade CSU prop.
Flew the 112 once; loved it, wanted it but couldn't buy it - guy had some issues with letting go of his aeroplane. He loved it too.
Pick of the litter for the Commanders would be the 115TC, comparable with the Bonza, so I am told.
Good points were the interior room and the solid build. Well appointed and standard avionics were pretty schmick for the day. Seats were very comfy and there are two front doors, plus the luggage door. Not real quick though; the 200 Arrow with the same engine ate it for speed.