I am off to EFT on the 6th April to complete 20 hours dual and 10 hours solo + Night for my PPL, over a period of 2 weeks.
I started on the ground exams in Jan and have been doing about one every week. I have now done 4 and passed with an average of 95% using both APMs and the Confuser.
If you live in London, you can do these exams at London Met Uni (Tower Bridge). There is a very nice chap called Bruce Abbot and he sets each exam for £30.
My advice would be to get the core exams (Nav, Tech, Air Law, Met) out of the way before hand and leave modules like Human Factors till last, or even do them in the US.
Good Luck!