I am using utorrent 1.4 and AFAIR utorrent also has the file integrity checking option but it doesn't check the file , when the download is complete , as azureus does .. But you may do a manual check of the file in that case for utorrent .

I'd say utorrent is best for slow systems and azureus for high-end ones , if you want to see more details on your download and that "eye of torrent" thingy in the swarm .