Might be their best. They were still pretty raw, not as produced as they'd sound later. Pyromania was the transition album and is probably my second favorite, and then by Hysteria they'd made the full move to over-production (IMO), but there are still several songs on Hysteria which I love.
I always wanted to love their first, On Through The Night, but it just sounds way too much like Ozzy Osbourne for me.