Widegon,
We use it on nearly all our machines.
It still isn't at the stage of extending TBOs etc, but has stopped some vibration checks that had to be done periodically, i.e. High Speed shaft checks on S61s and monitoring the 332 ones. It's reduced the vib levels significantly on the 332, so reduce the problems associated with that. It does track and balance every flight and you can do adjustments based on the redaings. Post Maintenance Inflight Tracking is also easier and quicker.
It has made the machines safer since now exceedances are recorded to the Nth degree, no longer was it about 850 ITT for a few seconds, it was 897 for 48 seconds. So we now know a lot more about whats happened.
Initally it was a pain but now it's just another piece of kit that is Mandatory on North Sea Machines.
Helps us anyway