I have had a faulty internal superdrive (Apple calls their optical drives superdrives) for the longest time in my MBP 13" Mid 2009. I want to replace it, but in my area it's pretty hard to come across a superdrive, be it new or used. I considered an external optical drive but quickly dismissed it, as it would be a pain to carry around and from what I've heard MPB's don't allow using external optical drives for recovering from CDs.
The next step was to check for any obvious signs of incompatibility. I looked at my MBP's optical drive, and sure enough, on first glance it looked like a standard laptop optical drive. The MBP Mid 2009 is decently upgradeable, with us being able to replace the shipped battery and the HDD. Unless there are some special requirements I am unaware of, I feel this is possible.
Another query I have is: Even if the optical drive works for general CD reading, will it work for recovery? Or will it act like the aforementioned external optical drives?
Please note: I have already put an optical drive caddy for an SSD earlier, and I didn't quite like it because it added extra bulk to the Mac. In the end I took the SSD out of the drive caddy and replaced the old HDD with the SSD. I removed the caddy too. It made the Mac much lighter. And yes, I have put in the faulty optical drive to check the weight and I find it quite a bit lighter.