The ADA4960 datasheet mentions:
"The buffered inputs of the ADA4960-1 isolate the gain-setting
resistor (RG) from the signal inputs, maintaining a constant 10 kΩ
input resistance, easing matching and input drive requirements."
Does this affect the behaviour of the feedback resistor? Can I use several gain resistors switched by a coax relay?
What is the best way to implement 2 or 3different gain settings?