wouldnt touch trillian with a barge pole. they have never been able to get file transfers working reliably, theres a serious issue with the pro version which means it uses a constant 10% of your memory bandwidth thus slowing the entire pc down, and for anyone that uses msn, it lacks virtually all of msns flagship features, i.e. proper webcam support, proper buddy icon support and any kind of custom emoticon support.
i have to say msn (msn 6 and up that is, nobody should be using anything older these days) is by far the best of all these im progs which is something if a miracle in itself since its made by MS, but i guess i can allow them ONE really good program.