Not sure which one to get. The price difference is not that much so cost is not an issue. I listen to everything except hip-hop and dance music, but mainly medium rock. Does anybody know which one is more suitable? I've heard that the 880 is more suited to acoustic material, and that the 990 can be a touch bright. BTW, I'm talking about the 2005/2006 versions of these 'phones and not the old ones.