I'll second what Util said. IMHO with needy list you can dump all those unit frames off your screen there is no longer any need to keep your screen cluttered with 40 ppls hp/mana etc bars that are first too small to read, second there being so many of them it's really impossible to really keep up on who needs what. Needlist puts bars on screen only for ppl that need something, buff/debuff/heal/res etc. It also tailers those needs to your class and custom filters you can set. It's alo great for you FPS in raids vs all those bars.
There is really no reason for everyone in a raid to use the same raid addon any more. Everything you need is avaible through blizz events and functions. I recently dropped from a raid group that was doing MC etc because they had a requirement to use an addon called RDX. IMHO RDX was getting more ppl killed than it helped due to the bloat and lagginess it caused. Buts a different topic.