need advice for dslr loupe viewfinder

[warthog64]

was wondering,
anyone here, that uses a viewfinder for filming with your digital reflex?

example,

http://www.cameratools.nl/GENG-LV-artik ... inder.html


wich one and why that one?

want to buy one, and need some advice, since I like filming with my camera (canon 7-D)

some examples,
[youtube]http://www.youtube.com/watch?v=jqgAgP4o4O0[/youtube]

[youtube]http://www.youtube.com/watch?v=EBCItooQSjY[/youtube]

made without a tripod and did not use a loupe on the lcd screen...