I really like this product. My practice space is also my home office in the garden, so it's pretty small by the time I get another four guys in there. We play mostly traditional Irish music, not amplified. In this context, the Rtom Black Hole system is absolutely invaluable - I get quite a bit of the tone of my lovely walnut snare (albeit muted), and everyone else can hear themselves play.
No one ever gets upset with the loud drummer - a revelation. When alone, I can take it away in 2 seconds, put in some ear protection and practice on my normal coated head at normal tension.
The ability to adjust tension combined with the solid dot area in the middle set this system apart from normal mesh heads - it's not exactly the same as a 'proper' head either, but it's a pleasant place in between. I enjoy the sound, I get to practice on the drum I adore (which I find an important motivation to practice) and I don't have to change heads and re-tune. I consider that there's enough tone and snare sound showing through that I can probably use this in a very quiet, acoustic live setting too.
It's really expensive, but underlying tone is retained to a reasonable extent, the quality can't be faulted and the convenience is wonderful. Really good if you have deep pockets.