I have no idea what they sound like live now, but in the early 80's they were fantastic. Of course they were LOUD (they stopped playing in 1983 when Roger Miller developed tinnitus (wonder how that happened) and didnt reform until almost 20 years later) This EP contains arguably their best music.
I didn't see them live in their heyday, but based on my fairly recent experience they were dread awful. They played loud but not super loud like some metallic bands. It was just noise, fuzz and drone. There was absolutely no melodic structure and the vocals were completely muffled within the sound. The sound was dense, which I guess is one of their trademarks but I couldn't make out what each instrument was doing. It was sort of the post punk version of free form jazz, which I don't understand either. I was with a guitarist friend who can play different styles and he didn't know what they were doing either. We both walked out before the end, which is the only time I did so in the past ten years.
p.s. I saw Superchunk the same summer right after they reformed as a band, with the same guitarist friend and we both thought it was one of the best concerts we attended that year. Superchunk was also loud, dense but tight with great hooks, so I'm not against punk or post-punk bands. In fact, I like almost all musical styles/genres so for me to be critical really is a rare occasion.