Raptors are too expensive for what you get. Not worth it at all.
Any of the Western Digital Black drives are darn good drives.
As well the new Seagate drives are also just fine.
Download the trial version of Acronis True Image to clone your drive to a new one.
It is fast, easy, step by step and simply works perfectly.
Brand, size, type does not matter, as long as the new drive is a least a large as the partition you are going to mirror to it. So yes, you can mirror you current 500gig drive to a 1 or 1.5 terabyte drive with no problem, at all.