I read Little Dorrit in 2010 or 2011. My notes at the time suggest I was not terribly blown away by the book. I'm not surprised. But, I loved it enough to dedicate a lot of time to finding the Marshalsea Prison wall on my 2012 visit to London. It's significance to the book, and Dickens' experience with debtor's prison, made it a must-see on the trip.
The one remaining wall of Marshalsea in London
Lil' D also spent a night in the church, which still stands nearby as well.