I think I am the person who would benefit greatly from two week challenges, because I'm so damn slow, but it's still better to keep it to one week, because it might encourage me to speed up a bit. I suppose the biggest problem is that we all have a life outside photochopping, so one week doesn't guaranttee any one person a certain number of hours, but I can understand that hosting a two week competition would be very dull.
An alternative would be to keep the one week challenges and then have a monthly challenge as well that people could work on when they had finished each weekly challenge. Again some people would have more time that others, some people would be faster than others, they are variables that can never be changed. I guess there is also the question of whether or not people would want to keep going back to the monthly challenge when they finish the weekly ones, it would have to be cars that really inspired people for them to want to keep going back to them.
