As with a lot of Milan's output I can't really say I love "Plastic People", but I think it's fascinating. There are hardly any songs of him I like from beginning to end, but most of them have moments of pure genius.
I think Milan's stuff is quite ahead of its time, as other '60s music from NY as well, although he never really leaves the field of pop music. It has moments that sound like 70s or 80s music to me, especially the melody lines. What I absolutely love about him is his over-the-topness. A bit like Phil Spector but with totally different means and instrumentation. Pop on the verge to noise. It's like: "Wow! How far can you go?!" I find that really entertaining, even amusing.
I got the "Hell Bent For Leather" collection and I think it's great to have a compendium of Milan's work on one record. It would surely be difficult to do that legally, so I'm thankful that a dedicated fan did it. The sound is pretty good, which is important, because the music itself is so exuberant and noisy already. Btw, exuberance is a good word to describe Milan's approach in general. I even like the cover art, because it reflects the flashy pop art aspect of Milan's music quite well.
The article is very interesting, although some minor information is incorrect or misleading. For example Larry Coryell has been in the studio prior to the Head Shop album more than once, not only with his band The Free Spirits.
The most entertaining part for me personally is of course the fact, that Milan is the younger brother of Petar "Radi" Radenkovic, the legendary goal keeper of the soccer team München 1860. Now it's the smaller team in Munich, almost struggling to survive, but in 1966 (!) they won the German soccer championship, when Bayern München was still a minor team. "Radi" was the hero of the hour back then. München 1860 is still the favourite team of many locals here in Munich, and some of my close friends are dedicated fans. One guy, his name is Axel as well, is even the official spokesman for the 1860 fans.
Anyway, I think Milan is a highly interesting figure. Somewhere between Phil Spector, "Wild Angels", glam rock, new wave & pop art. He also reminds me a little of his fellow New Yorker Marcus Uzilevsky aka Rusty Evans with his multiple reincarnations. And that guy is still alive. I wonder, has there ever been a thorough investigation about the "Psychedelic Moods" album or Rusty Evans in Ugly Things or anywhere else? Definitely a milestone in my opinion.