in downtown i'd go for meat company in souk al bahar - if it's all men they might prefer nezessaussi in the al manzil hotel - great sports bar. v casual.
Probably need a bit more info - do you want all inc, what area of Dubai suits best, is it all girls or mixed group etc etc
without knowing all that I'd probably go with
Barasti
Left Bank
Trader Vics
Bussola
Noodle House
La Verandah
Teatro