I have the stock 128GB SSD in my 2011 15" MBP, and also have a 750GB HDD in the optibay, which I installed right after I got the machine. Everything works great, but I need more space on the SSD (Boot, apps, Win7 via VMWare Fusion), so I'm going to get a 256GB SSD. I'm trying to figure out the fastest, cleanest way to make the new drive exactly the same as the old. I've searched, but I'm not coming up with what I'm looking for. I do regular backups using SuperDuper to an external drive (to a sparsebundle). I don't use Time Machine, but I certainly could. One idea is to back up the 128GB SSD to the optibay 750GB using Time Machine (I have plenty of space on the 750GB drive...). Then can I just install the new SSD, and restore it from that time machine backup? What is it booting from if the new drive is blank? Or do I boot to my SuperDuper backup so I have an actual boot drive, then restore the new SSD using the time machine backup? It was easy to format the 750GB drive because it was just the secondary drive. But I've never replaced the boot drive. I mean, how can I use disk utility if the boot drive is unformatted?! (Slap me if this is a stupid question.) I suppose I could remove the 750GB drive from the optibay and reinstall the optical drive so I can use a CD/DVD to do a fresh install of the OS. But that seems like a hassle. I want the new drive to be just like the existing drive, but with more space. Or, really, is the best way to reinstall the OS (I'm running SnowLeopard now), maybe go with Lion, and then copy over the apps and things individually? I know all about migrating stuff to a new mac, but never when that "new mac" is an unformatted drive on the same machine! Thanks in advance for your ideas!