Hi all! I'm considering if there are any detrimentals to buying a portable 2,5" external HD for my new 15" rMBP. Considering I'd hook-up my rMBP to its power adapter and do intensive video-editing / Photoshopping / gaming, having the 2,5" external HD suck out even more power makes me worried I'd be overstressing my rMBP. (Not in terms of blowing it up, but that the internal battery will be used to supply the extra power.) Perhaps, I'm wondering, it could be better to have an externally powered 3,5" HD hooked-up to my laptop - to relieve it from some stress? Of course, that'd mean less portability for the external storage. Any opinions here?