Pros
Lets be honest. Unemployment is now at 8% with 21% of 16-24 year olds unemployed. FDM gives graduates a chance in a time when it is very hard for people our age to find real jobs. OK the training is unpaid but myself and many of my friends form University ended up doing unpaid internships for extended periods of time- these were all at companies with no job offer at the end. At least the technical training gives you actual skills, as opposed to being good at getting coffee or photocopying. Also its important to remember that during the training FDM has salespeople (like them or not) working to find you a job. Yes the company makes money on each placement. I have never known anyone deny this. At the end of the day it is business and all businesses have to make money. Lets not be precious as a graduate we all have lots to learn and I have learnt a lot working at FDM. At the start of your career its about getting the foot in the door and then working your way up.
Kontras
The main Con is that you have to be geographically flexible if this is something you cannot do. Then FDM isn't the right choice. Also training does take 4 months unpaid, but as i said earlier would you rather spend 4 months getting better with real world skills or getting someone coffee!