Unpaid training, which can go on for far longer than you were told to expect, followed by 3 months of (unpaid) waiting to see if FDM can find you a temporary placement. You can be stuck going into FDM office ( as in you can't leave ) for over 9 months without pay - At the end of it you may get a placement or you may be released - luck and timing appeared to play a fairly large role, from what I saw, with regards to who got placed - I don't agree with the FDM comment on here "You can't polish a turd" as justification for not finding people work ( the people you found no placements for passed your entry 'tests' -)
Prospects after 2 years working for FDM not so good as you were told. You are not allowed to join a FDM 'client' for a year after your departure - unless you or your employer wish to pay a big wad of money. Since clients are anyone that FDM have ever placed any person with, the list is fairly large.
An unpleasant environment to work in - proper staff i.e. not I.T. trainees treat you pretty badly. This is throughout the company - HR, Sales, Marketing, Support staff, which led me to believe that this was an order from senior ( in every sense! ) management.
Pay is very very bad. You will do well to live on it in the South of England - commuting & rent are v. expensive - especially if you have to keep relocating.