Eh, I think sub-bass is pretty important. While you may not get it in the cases you mentioned, it's also not needed/expected. However, when you hit a song that's supposed to have some low impact and it's not there, then you have a problem. It'll definitely sound tinny/hollow. In the case of these headphones, I'm a little puzzled - on some songs, it seems like they've got oodles of bass impact, but other songs you definitely get that hollow/tinny sound. I've been fiddling with EQ settings to see if I can find something that fixes that, but my gut is telling me that these may have to go back.
I definitely love them for certain types of music - they're phenomenal on female vocals, for example - but to my ears, they push guitars too strongly. They remind me a bit of Grados in that respect, and I really don't like the Grado sound. The treble is also insanely bright. Earlier, I said it wasn't terrible, but in some cases, it really is. Screechy guitars and cymbals seem to set it off in a particularly ear-stabbing fashion. Bringing it down in a EQ tames it a bit, but I feel that if I'm having to resort to EQ past very minor tweaks, I should probably be looking at a different headphone.