I would have liked to see how it played out if the camera was hidden,I think the cops would have acted different. Also how's this play out of you are under the influence?
I think it depends entirely on the cops and how under the influence you are.
If the cops are respecting your rights and the law, this is a completely safe tactic to undertake to avoid giving them any kind of probable cause -- even if you have had a few drinks. You have a right not to answer incriminating questions, and you have a right not to answer any questions by the cops (except, in many places, your name and possibly address.) If the cops can't smell it on you, and you don't slur your words, and you don't give them a chance to try and get something out of you or see you stumble when you get out of the car or do their drunk test, well, they have no reason to arrest you or, legally, even suspect you. If the cops still pull you out and test you for DUI -- and arrest/ticket you for DUI -- there's a chance that your lawyer could get it thrown out as being a search without cause.
I think the camera definitely makes a difference as far as less hassle goes, but if you've got a good cop, you won't need it.
Unfortunately, there're a lot of bad cops out there who think the laws don't apply to them, so...I'd say your mileage may vary.