Almost a tossup for me. I like his 4 album in Van Hagar and I like a bunch of his solo stuff (but certainly not all of it). Going to abstain from voting.
One thing I totally respect about Sammy is his voice. If you've heard this guy on stage in the last couple of years, he can still belt it out like he did 20-30 years ago. It's like he got into his prime and never left it. I am not sure if that is because he took care of his voice or if it's just genetics and he never lost it. Can't say that about any other singer that I can think of, that sounds as good today as he did in the mid 80's.
Maybe Hetfield in some manner, but that is because he actually does care for his voice (which he didn't in the early years) and also because he changes his singing style when they recorded the Black Album. He's even said if he had continued singing like he did in the beginning, he never would have made it