I just can't help myself wanting to have the sleek MBA as my main machine. Being a value seeker, I can't justify spending $1600 plus tax on a ultimate MBA 13 and suffer the fast depreciation, but would feel little better with $1000 for a used 2010 ultimate MBA 13. I mainly use the MBP 17 for MS Office for Mac, working on web-based ERP, web browsing, light photo editing and Quickbooks on Windows 7 via Parallels VM. I don't play games on it or do heavy video/photo editing at all. I'll need to use an external monitor (24" or 27") with the MBA at work but using the MBA at home will be much easier than using the much heavier and bigger MBP 17. I find myself using the MBP 17 on a breakfast table all the time and hardly move it around due the comparably large size. I love the anti-glare high-resolution screen of the MBP and fast speed from i7 2.66GHz+8GB RAM+SSD but I don't think I need all that power and C2D processor and 4GB RAM may be sufficient for my needs. If I did get the used ultimate MBA 13, l'd probably keep it for a year or so and upgrade to a newer MBA then. Would I notice much slow down on what I do? Would 4GB enough for running Windows 7 on VM? I just don't want to downgrade to the MBA and regret it soon.