I have the Shooting Chrony, but with the fixed screen. I can see the value in a removable screen that you can read from the bench. I used it this weekend and it worked fine, as long as it was full day light. It would not work in the late afternoon.
I am thinking about the CED M2 with the infrared screen option. I want to shoot in my basement range and the Shooting Chrony definitely does not work there.
Also thinking about the Oehler, but it runs in the $500.00 plus range.