Hello, I've recently obtained a Mid-2010 polycarbonate macbook (A1342 MC516*/A; aka MacBook 7,1). It has been upgraded to 8 gigs of RAM. What is the best OS version to run on this machine? I am aware that it is capable of running Yosemite, but is that truly the best way to go for a 2.4 GHz Intel Core 2 Duo machine? I would be perfectly fine with an older OS if it meant better overall performance - less lag for example, or more stability. I do not mind paying for an upgrade/downgrade DVDs either. Clean install, fine by me. And yes, I am aware that the newest ones are free, while the older ones I have to order and pay for. The $20 or whatever it will take is not an issue. I simply want the fastest and most stable system for this particular model. I can live without iCloud, don't need anything else that comes on any particular version. As long as I can install MS Word, Dropbox, Evernote, Endnote x7 and access the Internet (with all necessary plugins for browsing today) I'm fine. Thanks for taking the time to read!