I expect to take a day trip to Macau during a Hong Kong stay, and I'm wondering about the most sensible way to handle currency conversion for some short-term investments at the roulette table.

I plan to fund the investments using $US, and I wouldn't expect to have any sizable amount of $HK. Am I correct to assume that I can use only $HK or $Macau to buy chips at the tables? If so, is it more sensible to exchange $US to $Macau inside or outside the casino? Or is there some other method that I'd overlooked. (I suppose I could find a cash machine/ATM, but I'm not sure what the daily $ limits might be.)

Thanks for suggestions,