Ease of use. However, I have a B&J 8x10 and it's not the easiest to use. In the front, it's not possible to change rise/fall without messing with tilt and vice versa. I like its ability to focus from both ends- front and back both have geared focus.
I'd like to get something that was lighter and easier to use but the price is right on the B&J- I own it.
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