If you are having difficulty with drop offs or sensitivity most of the time you can fix them by cleaning the inlet with a gun brush.
If this does not work, you can order the new Inert S/SL inlet parts
G3452-60570 Shell Weldment
G3452-60586 Insert Weldment
These are treated by Restek for us. The only drawback is that you CANNOT clean these inlets with the gun brush method/