My copperhead has very strong bass response, so I have to turn the lows quite a bit down to emulate the acoustic sound better. My lifeline is more true, but I still have to turn the lows a bit down. Since I started to use Ehrlund, I can use the lows pot on my amp as it should be - to compensate for the room; sometimes down, sometimes up.
To my ears, too much lows sound like too little mids and highs, which makes the DB sound like a cheap bass guitar. Be careful with those lows.
I never had full circle.
In my experience, the sound guys generally like too add some deep lows to the bass, to make the whole band sound stronger. I don't like it, but they do.