someone from work took his first test in barking in the second week of january.... around 9:30am test start
says it was quite a lot traffic on main roads, so he was taken to most the quieter roads (a lot of the one-way stuff), and was made to do lots of roundabouts on his test route.
.....he failed that test
however he tried again last week, this time in the goodmayes testcentre at around 11am (which has quite a few similar areas of barking route) and he managed to pass this time round
.....however my belief is if you're testing in or around east london then the hornchurch or hermon hill/wanstead routes seem easier ;D