OK, no evf but why not use this on nx200?

DSLR users have been using loupes on their dslr live view screens for a wile. Most are magnetic and clip on/off, so its not big shakes?

Am not hearing any dslr shooters moaning about lack of live-view evf, granted, they have an optical evf for stills. But still, this seems an adequate solution. So what are we missing;

Faster raw wright speed. Well, this is frustrating and surely Samsung can do something about.
AE-Lock addressed.
Am thinking nx200 at £400(body) in the UK is not be sniffed at and with a

http://www.amazon.co.uk/Magnification-LCD-Foldable-Viewfinder-Magnifier/dp/B004TDXMHM/ref=sr_1_1?ie=UTF8&qid=1326366768&sr=8-1

It seems to do most things?