Agreed wholeheartedly with FFF, I felt it was important to go straight from the groundschool brushup on the Friday afternoon (BGS in my case), into the weekend where you can have a mixture of relaxtion (hmm not very much as I remember but certainly the odd beer or two) and work.
I felt ready to hit the exams on the Monday, psyched up, fresh from intensive cramming, call it what you will, but ready.
I personally feel by leaving a gap of a week you will lose some of that intensity that you've just gained from the two weeks, and "come down" somewhat from the state of preparedness and readiness you leave the brushup with.