I have one. Very easy to drive, the whole signature is lean and the bass is just right, sparkly sound signature. They might be the same with the red dot normal ones because it's basically the upgrade on those, gonna buy one this month or next year and compare em since I'm almost complete with those 19-21 driver sets. Gets even more dynamic when you pair it to a warm source, even does imaging like crazy when you do.
The problem about these drivers is the steel mesh, I broke a pair just lifting those drivers off to a normal MX500 faceplate lol, but hey, it's worth it. Cheap too