I know memory is fairly inexpensive these days, but I think 4GiB of RAM is excessive. I did have a 2x1 dual channel kit in my laptop until one of the sticks went bad about a year ago. I never bothered to replace it, and I haven't suffered either. Right now I'm running a browser with several tabs open, a few shells in one terminal emulator, a couple of file manager windows, a PDF viewer, and an editor with a few tabs open (this is about all I typically use when programming), and I'm using around 615MiB-- a little over half-- of my mem and 0MiB of swap. I wouldn't have much to gain from another 3GiB of memory even if it is only a few dollars more.