[Elecraft] low pass filters

[Richards]

Good day -   What is the consensus concerning low-pass filters to 
minimize RFI both coming in and going out  of the shack?   Is there a 
type or size, brand or model that comes highly recommended?  Is it 
prudent to employ one, regardless of whether or not there is a known, 
identified problem , i.e., just in case?  Does it assist reception as 
well as transmission?

What is the real world skinny?

K8JHR