All of them seem to have different boost clocks out of the box. Does this mean that it's like the lottery ordering one of these cards? Do the ones with higher stock boost clocks overclock higher? My card (Msi gtx 670 power edition) has the lowest stock boost clock out of all the others I've seen of the same model, and I'm pretty bummed because of it.
It's normal for different companies and models to have different stock clocks. Often it just an overclock flashed to bios so it defaults higher , for appearance and for non-overclockers. Sometimes a specific model or series will acutally have better limits because of the parts. As for the lottery, no, the specs of what you receive should be the same as what you order, so just reading the listing.