My company operates a FDM system, and its a useful tool in my opinion. The data is analysed and any 'highlighted' data is looked at by a peer group of pilots, who are the only ones who have access to the crew names. If its unusual or worrying, they will contact the pilots involved directly, and discuss the case. The overall data is de-identified, before its passed on to training, Standards and flight management for what its best used for, improving the whole picture by identifying weaknesses in SOP's or other operations.
I fly without any thought to FDM, as far as I can I follow rules and stay with in the 'box', thus have nothing to fear. Any 'blips' that I cause should have an explanation,usually a crew report or ASR, because they will be unusual and I know it.
What it is good for is observing trends, and yes, to catch out the 'sloppy' or non SOP pilots... but is this a bad thing?.. no, and thats coming from someone who has a few years of bush flying behind me...
In my opinion, if you fly within the SOPs and generally stay safe, its a 'friend'.
Yes its a 'big brother' in a way, but it all depends how paranoid you are!