I have a 7" or 8" Le Creuset frying pan that I have used for eggs in the past -- typically when my T-Fal is dirty and I haven't had the chance to wash it yet. It does a fine job, if slow (because you're heating up all that cast iron). I use a little butter, more for flavor than any need to lubricate the pan.

My choice of your choices would be c. None of the above. Cast iron is good for things which either need to par-cook at very high temperatures (searing, etc.) or for long periods of time. Eggs meet neither criterion, so you're waiting to heat up a pan that really won't cook the food any better than a "lightweight." And I don't like the idea of heating up a non-stick pan to the temperatures required for searing. So I'd vote for another cheap-o non-stick for eggs unless you prepare them only rarely.