If you guys are up for the challenge of using the commandline, you can get superb download ability by using
get_iplayer. I've been using it for months and it work great, if on windows the binairy package should contain everything like ffmpeg, rtmpdump,etc
otherwise download
rtmpdump from rtmpdump.mplayerhq.hu
and ffmpeg from ffmpeg.org (or google ffmpeg binairy latest windows)
As said, I have been using it for quite a while on my mac (via Terminal.app) and I've already used it to downloaded over 160GB of TV series episodes of the BBC (technically it's more like over 120 because for programmes that are available in both SD and HD resolutions, I download both) so this past/latest Top Gear series 16 (broadcast between January 23rd and February 27th 2011) I do keep both, so for top gear that would be 630-odd-something MB for the SD-version and the 1,12/1,15GB for HD version.