Not only is it free but this plug-in packs an awful lots of features into it. HOFA could have made several separate plugins and they would have been very useful but this is overflowing with features.
Meter
Firstly it is a level meter, and they have included the EBU R128 loudness spec into it so the middle bargraph can be configured to read Loudness in a range of formats as well as momentary, short term or integrated EBU readings.
Level
There is a fader and also you can trim the left and right channels separately.
Pan
There is an interesting pan option that enables you to bring each side in or out, I suspect it is a new GUI take on conventional pan controls but I like it.
Mid Side (MS)
They have included an MS decoder into it so you can decode MS into LR or vice versa.
Buttons
Amongst the buttons by the side of the fader they have included a mono buton which is really useful to check mono compatibility if you don’t have that feature in your monitoring path.
Conclusion
So free and AAX Native, that’s a double result in my book. Go take a look at their other plug-ins too.