For the new imacs, i personally have a seagate. Which would you prefer out of the 3 Apple puts in their iMacs? I find it hard to believe, but if specs are correct, the seagate is the best, so its like giving some people better imacs without choice!! To be simple, if you could upgrade your HD, which brand would you pick? but in the poll say which kind YOU have, you can tell in the system profiler, for Hitachi people, it says hitachi, for western digital the model number starts with "WD", so seagate, your model number will start with "ST"