Ive had an iMac with an HDD and always was annoyed by how laggy it was. I thougth that having a computer with SSD would make it very fast. My Macbook is much faster than my iMAc but there is so little laggy moment when I scroll through iTunes. and it takes couple of seconds to open apps like pages. I atteched a vid to show you what I mean ... https://www.youtube.com/watch?v=oKlKwibj4tM is this the normal speed of SSD??? Or is this considered slow?