I would go ahead with the loop, because you can "personalize" them.
But I would make sure I had mechanisms that would allow me to recover if something happened...
That big of a loop... you never know what will happen.
For example, I wouldnt' store it in memory and just loop through an array.
I'd probably have a database or a text file or something. Have it delete the entry once it was set. Have another file telling where it stopped, what it's done... output everything.
Personally I think it's better than BCC.