Focus Assist LCD Goggles - anyone tried?

[pmgmedia]

Anyone ever tried using something like this for focus assist monitoring in the field?

http://www.reghardware.co.uk/2008/01/18/cinemizer_carl_zeiss/
or
http://www.myvu.com/
or
http://www.lcddigital.tv/video-goggles-silver.html

I know there are various levels of price/resolution/etc.. just wondering if anyone thought it was at all practical. Personally I like the idea of flipping down a pair of shaded goggles to check focus. Especially since they claim it appears like a 40" monitor. Any thoughts?

 

[someday]

Welcome to the future!
I always thought that in the future there will be no more TV posts.
Only video glasses, with ultra high definition, TRUE 3D VIEWING EXPERIENCE, and probably less waste.
WELCOME VIDEO GLASSES