One thing that made me change was the annoying “titles”. If you are listing your contacts by group it will slow down your client, this only happends in 0.97 version, in older versions I didn’t noticed this reaction.
About emesene I’m happy with it, it has the regular features that an MSN client should have and a couple of new ones. I can say that it is a Windows MSN clone without the crappy features.
It’s also written in Python, and that means it is portable.