This micro has been released in the 80s by AKG, in line with the BT 330 and other micros intended to compete with the SM 58.
It failed like the others, but this is more due to its price (about 3000F at the time) and the general conservatism of sound engineers (no novelty=no risk) than its quality, stunned
I use it for more than 20 years, primarily on voice, but it also does a good job on brass for example. (Off-axis)
The sound is superb, very warm, precise and with a flattering color for women's voices (a tad less aggressive than the SM 58), excellent internal suspension makes it insensitive to noise handling and pops, the look is special but I like it...
In short, unlike the SM 58 on stage, hollow voice, lacking presence: SM58, voice sonorous and well-tempered in the upper mids: D321