I have a feeling there are probably some other posts like this, but I had a hard time finding them when I searched mroogle. I love my 2010 15" MBP, but the stock hard drive is rather slow. Originally, when buying, I had planned on upgrading to a Momentus XT down the road, though with all the issues plaguing those drives, I've decided to hold off. 1) Revisiting alternatives, I've been seriously looking into doing an Opti-Bay mod and dropping in a 40gb SSD for my applications and OS, and keeping the Apple 320gb drive around for data storage. I really can't afford the Opti-bay mod plus an SSD any larger than 40gb unfortunately. 2) However, I can wait for the Momentus XT to be revised (and thanks to an article on Engadget, it looks like Seagate is trying) and I was wondering if grabbing a *fixed* 500gb M-XT would be better. 3) Option 3 is probably the best for battery life: Buying the largest 5400rpm drive I can find. I know I won't ever fill it, but the density of the drive will give me satisfactory speeds. (Mac Performance Guide article showing this relation) My question is really about the cons of these two options. What are the battery life hits each gives? 1) I haven't done a lot of research into what adding an SSD would do to power consumption, since this is a fairly fresh idea. This is also the least likely in my set up: I've never been frustrated with Application start times, and I never turn my mac off, so boot up time is relevant. 2) I've heard some people say that the M-XT really kills battery life since it's a 7200rpm drive, others have cited vibration issues. 3) Hard to find cons here, except for the fact that it's a 5400 rpm drive. So overall, what would you guys recommend? If you want to know my usage: Web/Software development with Aptana Studio, Eclipse and eventually Xcode (VS 2010 every now and then in Virtual Box as well), Adobe CS5 apps (LR, PS are the main two).