i realise the turnover is quite high in this industry...by hopping to competitors and then back and forth..

Many researchers seemed to be recycled between TNS, Nielsen and Millward Brown.

What is the inside story for career and pay progression for these big 3 really?

Does hopping to competitors provide a much larger pay/rank jump than staying at the same company?

What is the salary range for the various ranks?

Junior exec - 2.4K for freshies to 3K -3.5K for 2 to 4 years exp
Senior exec - ?
Manager - ?
Snr Manager - ?
Asst Director - ?
Director - ?