This is a very specific question about improvements from SSD (solid state drives). I've heard that improvement from SSDs are mostly in system and app startup boot times, but that SSDs don't make much difference to the actual running speed of the app. For me, Apple Mail is my main working app which I use for most of the day for office emails. A time-consuming aspect of Apple Mail is the time it takes to sync and update with Gmail. I have a large Gmail database, about 6GB, and have several Gmail IMAP accounts run through Apple Mail. In Apple Mail, if you click the Activity menu item, it brings up a window where you can see when Mail is synching with Gmail. Question: would changing to an SSD make a difference to the operational speed and, in particular, the IMAP synching speed with Gmail IMAP? I already know that SSDs speed up boot times and startup times. This question is specific to Apple Mail, Gmail IMAP and any benefit from using SSDs. I have a 2.8GHz, Core2Duo, 8GB MBP mid-2009 -- and recently bought a 2012 11" MBAir, 1.7 GHz i5, 8GB with SSD. Naturally the Air with SSD runs faster with Gmail IMAP, so I wondered whether that speed increase was more from the processor or from the SSD. The reason I am asking this is because I'm wondering if I add an SSD to the older MBP, would I get significantly faster Gmail IMAP sync, or would that only come by upgrading to a faster processor?