It comes with a balance knob?!?! I'll take it!

My old pre had one, my new one does not.

Interesting, when I had one, and utilized it, (rarely), I did so to figure out what was wrong with my set-up, in order to sound correct back to 'equal'. Well, now I don't have one, but really do the same. Set-up, set-up, cables, a speck of dust on the stylus, whatever, is usually the problem.

That said, yes, I have known those that had a set-up that really couldn't be changed for one reason or another, and in their case, they used it to 'balance' their imbalanced set-up or more importantly, room. So, for those instances it is probably nice to have.

I find it difficult as heck to find a balance control on a PC.

Does that make it audiophile grade??

I had an ARC Reference 1 and Reference 3, both of which had balance controls. Despite symmetrical set up, the sound in my room pulls slightly to the left. The balance control worked exactly as it should and was very useful. 

If you ever had a multi tubed preamp or integrated, you would find out very quickly as to why a balance control can be so important. 

I damaged my right ear drum at a Hot Tuna concert back in the '70's when  "The Wall of Sound" was popular (so why only the right ear you ask? It was at the Rutgers College Basketball arena and I was sitting on the right side with my right ear up against the speakers on that side) Anyway, it sometimes helps to make the right channel just slightly louder then the left. It's also the reason I like having defeatable tone controls. It may not be "pure", but it's all about the enjoying the music.