It seems to me like when I am trying to leech download a file, and the peer is running the old 2.2.1, the transfer speeds are extremely slow.
I know WHY they did that, because there were several versions of utorrent after 2.2.1 that had problems, but those problems seem to be gone (except with the blank line in the torrent issue which exists in version 2.2.1 also). There are a lot of people who insist on sticking with version 2.2.1 which is over 4.5 years old.