I am new to OSX and considering buying a new 2012 MBA 13" with i5, 8g ram, 128g SSD. 256GB SSD will be sweet since Win7 is necessary for me. However, $300 is way too expensive, I can't afford. So I was wondering if it is feasible to install Win 7 on a Usb 3.0 flash drive using PD7. ( I don't like bootcamp.) Then, everytime when I have to use win7, I can just insert my "win 7 usb flahs drive". Is it ok? Thanks. Note: what software I will use under win7? Pro/e 5.0, Labview, nothing else.