The strobes are very bright, indeed. I would imagine the fuel consumption is higher from all of that equipment.
The latest here (USA) is the "stealth" police car. No light bar on top at all. The lights are concealed strobes, and once you see the lights, it's too late...
Example:
http://www.angelfire.com/dc2/rwcar4c/morristwp.html (Although, the Lo-Jack array might be a giveaway...)
