There is just no exact science to it. It should depend on how well your application is prepared. If it's a strong application you "should" be on the lower end of the processing times but it's impossible to know for sure.
Here's an idea for you. Go to www.trackitt.com and compare timelines (average) for the two embassies. These are stats of real people. It might help you make your decision. But if you're looking for the "secret" no one has it as far as I know. And if they do they aren't sharing! Good luck.