best advanced unit building ?

[Crypt]

what do you guys think is the best advanced unit building to lvl to 10 ? ive just got the advanced air. considering either the dry dock or ground next.

[Oceanz]

depends on your nation

[Tctiger]

work out what units you want to buy next and do the upgrades , no point taking time to get a building to level 10 if you are not going to buy the units it unlocks , may be better off doing some boost or money buildings , i would make sure you have the upgrades done for the ltq events if you need those .

[Bala82]

depends on your nation

Yes this important thing only buy best units based on flag bonus .