Long time reader, but first time poster for this great community! I own a 15" Mid 2010 MBP and am looking to replace my optical drive for a SSD drive, but had a few questions: 1. Is the Samsung 840 Pro SSD worth it for my older MBP with only SATA II support? Specifically, I'm debating between a Samsung 256GB Pro vs. a 500 GB Evo. 2. Where should I install the SSD? It looks like it makes sense to keep my existing HD in its original slot and replace my optical bay with the new SSD because of the Sudden Motion Sensor. 3. Anyone have experience with battery life with this setup? How much percent decrease should I expect running both of the hard drives? 4. I use Time Machine for my backups. Once I have both drives installed in the MBP, is it possible to use Time Machine for both drives on one single external drive? Is there a more straightforward backup solution for Macs with multiple drives? Thanks in advance for your answers!