Is headphone listening a primary or backup for you when listening to music?

My RAAL SR1a are 2-channel speakers on my head. The closet you will come to 2-channel with headphones. Actually, there is another company in Europe that has a similar concept, but I never heard it.

The RAAL 1995 Immanis is considered one of the very best phones at any price. I love that phone too, but the much lower cost RAAL SR1a is still the champ for me because it gets me so close to 2-channel.

My RAAL SR1a is my second-best system, though my Mini Maggie’s (3rd best) are also high quality and I have them setup like headphones.

Like many, my headphone based system is put to use when my wife is asleep.  I really do enjoy it but loudspeakers offer me a far more realistic presentation of the performance.

I cannot respond with a proportion for headphone use is situational, based on whether other family members are working from home, or otherwise not in the mood to listen to my main system.  I do not have a dedicated listening room.  My living room serves that function, and my home is very average in size if not considered small for the NY tri-state area.  Until recently, I never listened to headphones for critical listening.  However, and with a shout out to @ghdprentice , following his advice in many posts, I purchased a respected, if not midline, dedicated headlamp (Burson Audio Soloist Stellar) of sufficient power to drive my power craving cans properly and have found cans can be magical.  So now, when the situation requires personal listening, I do not mind at all.  

 Secondary to speakers BUT mandatory in my living conditions..
 I will say however,the headphone circuit of my Pathos Classic Remix Mk.II is superb & compliments the 2 pair of cans I own perfectly so I never feel like I'm slumming when listening...

I use open planar HP when I want to listen to "acquired taste" music in a different room (ars nova, tromba marina, experimental "pop": Laibach, Bestial Mouths, Ethel Cain, etc.). Contrary to @mikhailark the planar HP (Dan Clark Ether II) do not have the spacial refinement of the speaker system in dedicated room. I also use IEMs (Westone Mach 80) in order not to disturb anyone, or to remove outside noise (airplane). Closed cans are too hot for me.

Just installed a second TT with my computer workstation, and enjoy it over speakers in a near field set-up. Not loud, but over speakers.