Carmen is probably a good system, but, like any computer system, it all depends on how you program it.
KLM 737 fleet have been using carmen for 10 years now, and the company is happy with it. Pilots are divided. (I hate it!!!)
They now tried to implement it on the 747 fleet, and "forgot" to add the labour agreement. It instantly cost the company in the range of 2000!!! extra off days to pilots before turning the system off again.
So make sure you are there when they program the system, and you shoudl be okay I guess.
Spuis