I’m in the same position roughly as you - applying for big 4 ACA in the hope of gaining a stellar CV and time to ride out the credit crunch before moving into other areas of finance in the next 3 to 5 years. I can only tell you what I have heard from others regarding this.
Basically, once you finish your ACA qualification it gets competitive. There are lots of other auditors out there who are bored stiff at the training they have just completed and are therefore competing for the high powered, more interesting and better paid jobs! Banks have the power to pick and choose therefore, and typically people stand a better chance if they have passed all their ACA exams FIRST TIME, with good marks. What I hope however is that in 3 to 5 years, when the banking sector is picking up and entering a new boom period there will be lots of gaps to fill and ACA-ers will have less trouble than they have had in the last few years.
I know someone vicariously whose CV looks like this:
Audit ACA, big 4
Moved into corporate finance on qualification, stayed 2 years
Moved into a more senior corporate finance role at another big 4 firm, stayed 2 years.
Moved to an investment bank front office, stayed 1 year
Moved into a hedge fund for several years, hedge fund just went bust in the current recession
Just started a new job at a private equity house.
Obviously this guy is an extremely successful example - he is a millionaire and has scope to earn many more millions. We aren’t all so lucky and we aren’t all in the right place at the right time to receive these opportunities! But this just shows where the ACA can get you, and how wise it is to take the short term cut in salary compared to other grad roles such as law. The long term remuneration for qualified accountants can be seriously impressive.