The Need: Unfortunately, I need to use Windows to run Bloomberg Pro and some decently large models that pull both live and static data from Bloomberg BDP calls. Speed is important, but not crucial. It can be done in a VM, and that's my preference, but from time to time I may want to boot from Bootcamp as well. The Plan: Get a 16GB/256GB rMBP + 400x 128GB SDXC card. I only use 120GB for all my non-Windows stuff, so a 256GB drive should leave me with room enough to grow. The Windows stuff will be much less than 100GB, but I'd like to have more than 64GB dedicated to a Windows partition. Was thinking I could partition the card as a Windows drive, put Win 7 and the Windows software on it and use it for both Bootcamp and with Parallels 8. The Reasoning: I don't need (nor do I want to pay $500 for) the 512GB Apple flash drive upgrade. I do want a little extra space to separate Windows from my OSX hard drive completely. And I'd like to have it be very portable (more portable than a portable external HD). Thus, I thought that using an SDXC card would be ideal. Anyone done this? Any thoughts on whether or not it'll be fast enough? Any other downsides of which I should be aware before diving in? Thanks for the advice.