Hi QAR
I don't know exactly what the F/Os manage to take home every month, however if you look at this link then you can probably work it out:
http://www.ppjn.com
You need to multiply Bahraini Dinars by 2.65 to find the USD equivalent.
Time to command has recently been about 7-9 years however they will be moving faster than this in the near future as there are no more DECs at the moment.
Finally, yes they do give a Housing allowance, mediacl benefits etc.
Good luck
Che