An intersting thread, though I would disagree with the adjective "lumbering" for the Lancaster (nice bit of alliteration though). With the drag from aerials on the nose array of the Bf110s, there was not a great deal of difference in speed, as Heinz Schnaufer acknowledged in his post-war interrogation. See the quote from Harry Cave on my website about his view of flying a "lumbering Lancaster":
http://www.galgos.co.uk/54401/index.html
Regards
Max