Switched from AntiRSI a couple of week ago.

I find the visual activity as a very helpful reminder to slow-down, relax and fix posture.

This is a very smart program. I've tried similar programs, but ended up skipping the breaks or quitting because I found them too jarring to my workflow. MacBreakz does not force you to stop working for a break (unless you set that as a preference). It knows when you are working and it watches your keyboard and mousing activities. It suggests micro-breaks (mine are set to 5 seconds) if your activity reaches a dangerous level. And the regular stretching breaks are customizable (I do one every 30 minutes, for 3.5 minutes). The program detects "informal breaks" and restarts the interval countdown. Very smart!