I am planning to replace my base model mid-2013 11" MBA. I do not have any other Macs. I use the MBA on the go, at a desk with an external monitor and around the house. I use the Mac for managing photos and videos, for email, web browsing, reading, word processing, etc - nothing special. My Photos library is 168GB with 30,000+ photos and 1,000 videos. It does not fit on the MBA's 128GB SSD anymore. I use iCloud's 'optimized storage' on my iPhone, but I want the Mac to keep a local version of the entire library. So, my Photos library lives on an external disk. The replacement for my MBA would need to have more internal storage. I would go for 512GB. My other complaint about the MBA is the wide aspect ratio / limited vertical resolution, especially for browsing and word processing. This is not a problem when the MBA is hooked up to my 24" external monitor 1920 x 1200. I do not want to add a Mac mini or iMac to my MBA, because I want to keep a laptop and I do not want to manage / sync two Macs. So, here are the contenders: 13" MBA: undoubtedly meets my needs, and I would have a 1440 x 900 screen to work with, but why postpone the appealing upgrade to retina for another couple of years? 13" MBP: Once I go for the 512GB version, there is no need for other upgrades. Probably most future proof (also considering the ever expanindg Photos library). But almost 50% heavier than my current 11" MBA... 12" MB: Great form factor: even though I no longer want the 11" MBA, I do appreciate how small and light it is. I think that I am willing to deal with the single port. I would try the 1440 x 900 scaled resolution, but I am not sure whether that would work for me. I am a bit worried about performance. I suppose the CPU will be slower than my current MBA. On the other hand, I would go from the current 4GB RAM in the MBA to 8GB RAM... What would be the net effect on e.g. the performance of scrolling through my Photos library? Looking forward to your advice!