In my circumstances this device has made a big difference to the clarity of my headphones and so the enjoyment of producing / mixing. It is more fun now I can hear better what I am doing.
I was using my 38ohm headphones out of the interface outputs (Steinberg UR816C) and had felt for some time something was off, even using Realphones (speaker sim) plugin the base sound was poor quality, but I did not feel it was the headphones at fault. It turns out that the headphone output of the UR816C is either 40 or 90 Ohms depending on the source you read. Let's take the minimum of 40 and to get reasonable sound your headphones should be 320ohms! This is the rule of 8, for headphones. So this is a huge mismatch trying to drive my phones when the Ohms are so close in rating. It produces a cloaking of the sound and minor distortion.
Now with the Cranborne N22H we have a headphone output of only 0.33ohms. now with my 38 ohm headphones there is way more headroom and they are being driven by clean power with no distortion.
The result is fantastic, literally like a cloak removed from the sound. The most blatent example was listening to a favorite track that is only sadly a mp3... Previously I could hear minor annoying artifacts of mp3 encoding but not enough to spoil the song... Now with N22H I had to stop the song, the mp3 artifacts I could now hear fully and it was terrible. I expected a much smaller difference so I'm delighted to have a rather large difference. Everything is so much clearer... Bass sustain, reverb tails, delays. It's remarkable the difference. If you are running headphones in the 30-60 ohm range straight out your interface (even RME interfaces headphones outputs are around 30 ohm) then you could investigate and consider this product. For the price it's outstanding, and even if more pricey still a solid choice. Of course if you are using high impedance 300+ ohm headphones, you likely will not have the big difference as I had as you don't have such a big mismatch as I had.