Originally Posted by
watercooled
250GB will almost certainly be single platter. 500GB platter drives are the norm now. There's little or no point going with SATA 3 although it's the only choice with some drives, just don't let it influence your decision as I don't know of any mechanical drives that can saturate even SATA 2.
You will hear bad things about all of the MFRs if you look, I don't think there is a simple answer to who makes the most reliable drives, but backups are crucial regardless. Also consider Hitachi, they had problems with drives like 10 years ago and for some reason, people still avoid them because of this when in fact they make some of the best drives out there and were one of the first (or the first) to offer 7200rpm 2TB drives.
TBH you'll probably find 500GB drives for about the same price as anything below that now.
About quietness, it varies even within drive models/capacities and between individual drives. Check our SPCR for some ballpark ideas though.