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Those digital microscopes are a PITA to use to see edges. If you can figure out to keep the blade steady while looking at it, then they will work decently IMHO.
Thing is when honing, you'd need to...

Here is one that is very reasonably priced and has metal body (hopefully a sign of not being cheaply made otherwise)
10X-20X-30X-60X Sharp Stereo Microscope + USB Camera

I planned to get it to...

mine is 30x and works great for me.
I also have 30x -60x but it has blue LED that annoys me. It also requires constant focus adjustment so it stays in the drawer as a back up.

I use this one
http://i1020.photobucket.com/albums/af323/mainaman1/Knives/Razors/scope_zpsebcea1f4.jpg

can be found on Amazon, my first one I got from ebay.