I'm trying to decide between two wildly different computers. Currently I have a 2.26 C2D 13" MBP with 4 GB of RAM and a 128 GB Intel SSD. I'm doing the following things with it: Textmate for LaTeX writing iTunes with tunes playing Chrome with 10ish tabs open Papers with all my academic literature iCal Mail VMware Fusion running Windows 7 for coding purposes in Visual C++ Right now the fan is running constantly, switching between apps is sluggish, and my computer hangs for 10 seconds at a time twice an hour or so. It doesn't help that my simulations in Windows take forever. I should point out that my simulations are single threaded. I'm trying to decide between a base 13" MBA, or a somewhat tricked out 15" MBP with 8 GB of RAM, the upgraded resolution and the same SSD. The difference is $700 and some change, I think. I love the portability of the MBA. My wife has an old one and she takes it everywhere in the house or outside. I imagine that if I had the 15" I wouldn't take it with me on the couch too much, which is a bummer. That said, I like the idea of the performance of the MBP. Mostly, I worry about the 4 GB RAM limitation of the MBA. In fact, if the MBA could be ordered with 8 GB, I don't think I would be having this decision right now. That said, geekbench says that the MBP is much faster than the MBA, and I'm wondering if it's the kind of performance I would appreciate for my uses. I don't need an optical drive, I don't need large amounts of storage, and I don't play games. I'm not considering the 13" MBP because the resolution is too small (I have an external monitor now, and would be giving it up for the upgrade). So, what would you choose and why?