10 minutes for sure. We play a weekly game at the local hobby shop and it drives me nuts when some chowder head spends 20 minutes trying to figure out where to buy then another 20 minutes where to attack. Arrrrggggh! I usually loose intrest in the game because it is so hard to stay focused.
the dire rolling and combat resolution should be unlimited, after all there can be some pretty big battles out there and there may be times when you have to think hard on wether to push the attack or break off.
But yea 10 minutes for every thing but combat resoultion.