I have been getting a bit impatient with the 5400 RPM 1TB drive in my mid 2012 (model 9,1) unibody MBP lately and so am considering replacing the current HDD and optical drive with a fusion drive. My plan so far is to purchase these three items: 750GB 7200RPM HDD 256 GB SSD Mounting bracket for SSD and to sell the current internal drive and optical drive on eBay (and maybe buy an external superdrive). I would follow one of the many tutorials online to create the fusion drive so that it is managed by OS X. I want to make sure that all of these items will work together and that the SSD I'm purchasing is a good one. Also, do you think that the speed increase I see will be significant (so that I don't regret the ~$100 it'll cost (after selling the current internal parts) and the effort)? Is there any significant decrease in battery life to worry about when running both a HDD and SSD? Any thoughts are appreciated. Thanks!