submitted ppi claim, got an offer from bank,is it wise to accept or say no to first offer and go to ombudsman?

[Marky]

completed proper ppi claims form to several banks and have recieved an offer of settlement,is this offer usually a good and honest offer or are they holding back and should i refuse and apply to the ombudsman to take a look and hopefully get a greater amount back,and if i did this and the ombudsman agreeded with bank do i still get the original offer,i have 14 days to reply. basically as none of us trust the banks are they trying to screw me and palm me off with a small offer when i am entitoled to more. thanks and happy new year