Hi Ken,
If you do a search you will find many of your questions answered.
Just a few threads from typing in "rifle basix trigger" into the search.
http://savageshooters.com/SavageForu...c,36389.0.html
http://savageshooters.com/SavageForu...c,34347.0.html
http://savageshooters.com/SavageForu...c,37440.0.html
http://savageshooters.com/SavageForu...c,37936.0.html
http://savageshooters.com/SavageForu...c,30569.0.html
http://savageshooters.com/SavageForu...c,29188.0.html
http://savageshooters.com/SavageForu...c,15096.0.html
http://savageshooters.com/SavageForu...c,29745.0.html
http://savageshooters.com/SavageForu...c,27586.0.html
Now after reading all of that you could do a search on "SSS triggers" or "sharp shooters supply triggers" and find more information.
In closing if you want a trigger for "Competition benchrest use" then the SSS evolution is your best choice.