Got a Macbook Pro 15 inch from 2010. Inside it's got 8 GB of ram, a 2.8ghz i7 processor, and a Crucial SSD running Mavericks. It runs great! Couldn't be happier with it. However, I'm getting the itch to play with Yosemite, give it a test run, etc. What I thought I would do is pull the SSD and replace it with the original 5400 RPM drive that came with the Mac, then install Yosemite and play around with it for a while, see how I like it. Before I do all that, I'm just wondering, how does Yosemite run on a 5400 RPM drive? Is it usable, or am I wasting my time installing it on a 5400 RPM drive? Thanks.