[Yussef]

I wouldn't worry about perfect gear before starting MC, stuff like Quel'Serrar and Breastplate of the Chromatic Flight are not needed. Spineshatter, Bloodlord's Defender or Fiery Retributor are quite comparable to Quel'Serrar anyway. If you consider a passive effect vs proc rate and duration etc.

Aim to get the Overlord Ring set, Aegis of the Blood God, Bloodlord's Defender and some of the Bloodsoul set, namely the boots and perhaps the shoulders. Wouldn't 'waste' time on non raid stuff really if you have the chance to do Onyxia, Molten Core and Zul'Gurub. At least you have a good chance of upgrading your character.