All the time since there is no perfect room and therefore, even if you are the best set up guy in the world and have added reasonable acoustic treatments, EQ for minor, final fine tuning is icing on the cake. Every LP and CD you own has been EQed many times before it hits your home; no debate like you find among audiophiles in the recording/mixing/mastering industry.
I'm saving for a Manley Massive Passive (I can also use it in my studio) for analog and I do my final EQ for digital using the EQ and room correction algorithms in my Weiss DAC501.
IMHO, the Schitt EQ products are a gift to all audiophiles. The Lokius with six bands is where I would start. I tell everyone who will listen to pick the one in their price range, play with it for a few weeks and return it if it isn't for you. Nothing to lose and a lot to gain.
This will horrify dealers though. In many cases trying EQ is likely to stop the silliness of trying to EQ your system with cable swaps, component swaps, funny things that go under other funny things and so on.
I'm beginning to think that the elimination of early tone controls (yes, I know, cheap parts, bad circuits but why throw the baby out with the bathwater) was a savvy idea in the early days of high end to keep folks changing gear when all it would take is a few turns of a few knobs.
Anyone that can't/won't optimize speaker and listening position per Jim Smith's Get Better Sound or any other tried and true method must try one of these. I insist. Cult leader Jason Stoddard can thank me later.