The other things to consider is that these assumptions are based on a 5 year period. Two thoughts on this:
a) Will FlyDubai last 5 years (right now thats a BIG question), if it went out of business you've lost your sponsor and must either get another one or leave the country within a month - this can be VERY disruptive if you've got kids in schools etc. Just look at how many people have left/been forced out recently....
b) Are you 100% sure that you and the family will last 5 years? Dubai isn't the dream that many people think it is, have a look at all the posts about the place, all that glitters isn't gold.
Don't want to sound negative but make sure you know what you're getting into.
Best of luck, hope it all works out
