This morning i was playing and was my first try I didnt think i had over 95% then at the end it said i had somthing like 95.68% so i was very lucky! And i got the Laser assassin achievement finally!
Oh and I didnt use any overdrives so i props could have gotten even better with overdrives!
This video helps a lot:
http://video.google.co.uk/videoplay?docid=-435065682899786051Already been posted before but just for the people who cant find it