I have a mid-2011 MBAir 11". 4 GB RAM, 256 GB SSD, 1.8GHz i7. Loved it and used it a lot, but a few years ago, the battery was dismal, so I purchased a replacement battery from iFixit. I noticed the battery seemed a bit dusty and after I installed it, I was quite disappointed. I thought I would back close to my 5 or 6 hour run time, but it only lasts about 1.5 hours (maybe 2 hours) before the battery is depleted. I suspect I got an original battery that might have been sitting around for several years... So, for the last few years when I travel, I've been managing with either an older 13" MBPro (pre-USB-C) or else one of the newer 15" MBPro if lightweighting isn't a concern. However, I have a longer overseas conference coming up, and weight/bulk is going to be at a premium. I'd like to be able to do some serious work if needed (manuscript writing, editing documents, etc.) and backing up and even light editing for photos I'll be taking in-between conference activities (I'm a pretty serious photographer as well). My options are: Try to do everything with my 12.9 iPadPro. I will probably bring this along anyways for note taking, etc. Not sure if I can do everything I need with just it however. I prefer a notebook to do actual work (editing documents, etc.). Get a refurbished 12" MacBook. How would the new generation MB compare performance wise to my old MBAir? A lot faster, slower, about the same? I like the new 12" form factor, but I'm not keen on the new keyboards (I don't really like the one on my 15" MBPro), and the fact that there is only ONE port on the MB kind of terrifies me (hello Apple? redundancy?). And I'm rather tired of the whole dongle workaround... Get another battery from MacSales for my MBAir, put that in, and see how the power performance is. Given that a replacement battery is less than $100 US, this seems to be a low risk option, but I'm cognizant that I'm putting money into a 7 year old machine now. NOTE: I notice that the fan seems to kick on my MBAir sometimes, and unnecessarily so: I'm not sure if it needs some sort of calibration, etc. I tried calibrating it before but I don't think it made much difference. I'd even consider other options (such as getting a super small, underpowered Windows notebook or UMPC to handle things like file backups and transfers and access to a full OS, while getting by with my iPad Pro). Any advice appreciated.