on an 85C, the SAO trigger can be set up exact same as an SAO 75 Shadow or SP01 Shadow.
very short trigger movement both in letoff and reset and be in the 2.5# range or better.
sights..if I was spending money. I would look at having something milled in..either adjustable or with a lo-mount cut.
or go with the CZC tactical rear and FO front.