Anyone using these?
Seagate Slim Portable Drive for Mac
http://www.seagate.com/external-hard-drives/portable-hard-drives/standard/seagate-slim-mac/
That one isn't USB 3.0, but the other one below is and even has an NTFS driver for Mac pre-loaded on drive, though it may be best to format it HFS, unless wanting to share it with non-Mac computers
Seagate Slim Portable Drive
http://www.seagate.com/external-hard-drives/portable-hard-drives/standard/seagate-slim/
This looks like a really good drive from the specs (I even think the disc is 7200rpm, which I'm not sure the G-Drive Slim will be), and I've seen one of these drives in a store and its very small and slim.
I'm still hanging on for the USB 3.0 G-Drive Slim, though, as I prefer its appearance, matches the MBA better...