I'm using them on the Arduino Mega 2560 Rev 3. What do you need to know?
I'm working with one so far. I mounted it on a servo in an enclosure. When it detects an obstacle, it looks left, forward, and right, then will move my robot in the direction with the most clearance. I just finished testing it on my desk, and it's ready to install on my bot. You can see the video of the test at http://www.johnlizotte.com/robotics/testing-servo-mounted-ultrasonic-sensors/
. (Sorry I don't know how to embed it here or compress it enough to post here yet).
Once it's mounted and my code is tweaked, I have 5 more of them to install.