I've not had any problem with Yahoo. Very little spam ever gets to me. I use hotmail as a junk addy, that's where all the spam goes.
Better in my view, as nothing ever gets down to my machine unless I actually download it.
I'm still riding my "never had a virus, mole, or trojan on this machine" record.
The sieve-like security on most of those cited mail clients leaves a lot to be desired.