The good: - Adhesive patches were exactly the right size to adhere the SSD to the case behind the ODD without bumping into it or covering any labels on the SSD; - The kit just worked, first time every time for each installation I've performed so far

The bad: - SATA cable connector really needs to be right-angle in the appropriate direction at the board; straight connector gets wedged really tight, which makes my job harder as a systems admin/builder; - The SATA cable could also be a bit shorter (possibly 12"); there was at least 4-6" of unnecessary cable that I found I needed to pack into the case; and - Needs to be a little easier to remove the protective film from the adhesive patches; I often found myself pulling up bits of the adhesive trying to remove the protective film.

Overall, it's a great way to breathe new life into older hardware; our 2011 i5 iMacs upgraded with 20GB RAM and a 740GB Fusion drive perform comparably with our more modern i5 and i7 iMacs in boot speed, launch speed and overall performance.

I would recommend this item to a friend! Customer Videos:

I would recommend this item to a friend! Customer Videos:

I would recommend this item to a friend!

Patience is a virtue during installation. I also recommend wearing thin cotton gloves when removing and reinstalling the display panel. That makes certain that you will NOT get any fingerprints on the display surface. I also used a can of compressed air to remove accumulated dust from the fans, and a cloth to wipe the back of the display and internal surfaces that had collected dust during my first 18 months of ownership. The heat-generating components inside the 21.5" mid-2011 iMac require cooling fans and plastic shrouds to direct airflow. All those parts fit together with precision, and once taken apart, all these pieces will only go back into place with patience and a bit of fiddling. I found that removing the upper right of the plastic airway shroud behind the motherboard and then easing it back into place WITH the motherboard during reinstallation made it much easier to return everything to the proper location so the motherboard assembly could be aligned and screwed back into place. The installation process is not particularly DIFFICULT, but there are many many steps and many thin wires and cables with tiny connectors that first must be carefully disconnected when disassembling, and then carefully reconnected during reassembly. Yes, they COULD be damaged if mishandled. If you are experienced in taking modern computers apart and reassembling them, then go for it.

It is a HUGE help to have another computer right there to play the OWC installation videos available on YouTube. I had my retina MacBook Pro on the desktop beside me, and was able to view and replay the video as often as needed. In all, I took my sweet time and spent about 2 hours doing the dual upgrade - SSD and hard drive with OWC sensor cable, not including time spend installing Yosemite on the SSD, nor cloning the original HDD to the new one. Reinstallation went smoothly. I plugged it in, turned it on, and the dreaded 3 beeps! I somehow managed to transfer a tiny bit of the adhesive from the SSD foam tape onto a finger and onto one of the RAM module connectors. Powered off, and a quick inspection and thorough cleaning of the RAM connector, reinstalled, and the system booted normally. Then I noticed a tiny dark semicircle at the bottom right of the screen near the Trash icon. I wondered how I could have cracked the display glass in such a perfect semicircle while gently wiping with the lint-free cloth. I used the suction cups to again remove the front glass panel for a closer inspection, and reallized I had gotten a piece of blue thread (from the lint-free microfiber cloth, apparently) on the display. A flick of the finger, and it was gone.

I would recommend this item to a friend!

I would recommend this item to a friend!

I would recommend this item to a friend!

Instructions are easy to follow and end result is a much faster Mac. Very happy with the purchase.

I would recommend this item to a friend!

I got to work. This was my first install of an SSD in an iMac. The video tutorial is what made me choose OWC. I really appreciated the care that was put into making the video. It was so easy to follow along and imitate what was being done.

I really suggest this upgrade to my fellow iMac users. It took me 1.5 hours to complete. There are some areas of the project that are a little scary but nothing too bad. The end result is an upgrade that makes it feel like you got a new Mac.

I would recommend this item to a friend!