Why did I start with them? Why do any of us choose one company over another as an employer? The money? At the beginning they all offer more or less the same and no one know how it will go after that. I guess it is often not so much your prospects at a particular firm, because these are essentially unknowable, but whether people will think you have done well to get the job there, that determines you choice. That was largely it in my case. It was really the prestige. They gave good letterhead.