I know there have been several posts about booting imac from external SSDs. Recently I have been doing some research on which external SSD to get, and it seems like the LaCie Rugged SSD Thunderbolt is the safest option. However, i also came across LaCie Porsche Design P'9223 Slim USB 3.0 120GB Solid State Drive - it is US$50 cheaper than the Rugged but with no Thunderbolt. Does thunderbolt really matter given USB3 has pretty much similar read/write speed. Has anybody tried this? Any thoughts? Thank you!