It is very important that you bring your wife with you for the interview. If she gets here and decides she hates Dubai you will be very miserable and commuting from America is not an option. While you are being assessed she will have a chance to look around the supermarkets/shops etc to get a feel for the cost of living and you will both be able to decide if you can live on an F/Os salary for the 7 or so years an upgrade will take. (It can be done but it won't be an extravagant lifestyle.) There is a good website called
www.grapeshisha.com which has some excellent and accurate spreadsheets about the cost of living in Dubai.
If she want to work get her to have a look in the appointment section of the Gulf News so she can check out what she might earn.
Have a look at the Properties/Freehold section in the same paper so if you end up hating the company villa/apartment (I didn't like it and moved out within about 6 months- that can be a saga in itself) you can see how far the utilities allowance (as it is called) will go. The answer will be not very, but for me it was a quality of life issue.
Finally, by the middle of next month we will all know about this year's profit share and payrise. That should help you to make a decision.