In honor of the soon to be natural phenomenon that seems to be driving the Internet out of its tiny mind;
It's very rare for heavy metal bands to get better as they age. Bands like Dream Theater, King Diamond and Iron Maiden have been very consistent releasing quality music their whole career. Bands like Metallica, Yngwie and Megadeth that regressed terribly. But than you get bands like Blind Guardian, Testament and Manowar that have done or are doing some of their best work later in their career.
I have been a Keb Mo fan for a lot of years, but only really recently realized how much I love his stuff. They call him a bluesman, but he sure makes me happy.