Have to be careful what I say here as we arrange DMP's as well as IVA's so I can't promote, as it were, so the answer to fee paying or non-fee paying is really one only you can take.
All DMP's incur costs, it is just a question of who pays the costs. For a fee paying organisation it is the client, for organisations like CCCS and the like it is the creditors. You will read many bad things on here about the CCCS and how "he who pays the piper calls the tune", as well as CCCS guidelines etc, but you will also read many good things as well.
Similarly, you will get tales of woe re fee payers and hearty recommendations also. All I will say on this is that if you do go fee paying then, at the very least, make sure you pick an organisation that will not charge you any extra for switching from a DMP to IVA if and when the time comes. Preferably, you should look for one that will refund the first payment on a DMP, which is typically kept to cover start up costs, into the IVA to kick start the IVA process.
As for the previous job situation, I will review that as soon as I can internally.
Regards.