How many quarts of oil do you use?

My car uses oil and I'm 99.999% sure the PCV is sucking it into the intake. I've done a compression test and it's not the valves and there are no leaks.

In regards to quantity for an oil change, my last oil change the car used a little more than 5 litres but that was probably due to the K&N oil filter which is a litle larger than the regular sized filters.

I just got back from an emissions test and the car passed BTW. Thank god because this was the 1st test done since the engine work.
 
My car leaked from the Oil Sending Unit pretty badly (a common problem with Fords after talking to several Ford Techs) and the drain plug gaskets were both worn out so I replaced those.. And now it does alright. I'm going to replace my PCV valve here soon. Just for the hell of it.