Ermz
¯\(°_o)/¯
I notice a lot of guys here are going for some older productions, maybe out of nostalgia or for whatever reason, but I'm inclined to agree with you Ermz, that using productions with such a high level of technical perfection are a better way to go than say, the Black Album or Jester's Race.
Yes, it's very important to divide subjective musical opinions from production tastes or distastes. It's very difficult to do, as the two are so entwined. Looking at these productions on a purely technical basis will unveil something entirely different to seeing the entire picture, music and all.
STD, for instance, is absolutely atrocious musically. One of the worst metal records I have in my collection. Just coincidentally happens to have what I consider to be the tightest production job in the genre (that I've heard thus far anyhow).
I admit that Clayman is probably in there partially due to nostalgic reasons. The production may not stand to the most modern records, but there is something endearing and 'real' about it. I love that analogue feel, and it's a vibe that is largely missing from newer metal records. There is a sweet middle ground there which hasn't been thoroughly explored IMO.