Hi all. I've noticed that if I run iTunes, Safari and Word at the same time, my Mid 2012 MacBook Pro becomes sluggish. It has 4 GB RAM and is running the latest OS. I'm guessing that in not too much time the MacBook Pro will gradually become unsupported from future updates, especially since it just grazed through the continuity feature released in Yosemite. My question is, should I upgrade the ram to 8 GB - 16 GB or wait it out until I purchase a new machine in 1-2 years? Thanks!