All of this "good for rock" and "good for metal" nonsense is based on the very narrow-minded view that there is only one acceptable bass tone for any given style of music. This is utter bollocks. The current craze in "nu-metal" and other contemporary rock styles seems to be for basses with a huge midrange bite at the expense of low end, and gritty amp settings. But if you listen to decades of "rock" leading up to March of 2010, you will find a ridiculous variety of bass sounds used in the genre's history. None of them is more "good for rock" than another. What's "good" for any style of music is finding a tone you like and setting yourself in the mix with your bandmates.
I play a Stingray 5 fretless set up with a fairly aggressive tone in a country/folk setting. I get great comments on my sound all the time.
But if I asked around here at TB, most people would say "a fretless Stingray 5 is not 'good for country.'"
I think such pronouncements are only applicable to players with mediocre skills and immature ears. If you've got the chops, you can make just about any bass work in just about any situation.
Never did I say that only one bass is acceptable for any style. Some do it better than other... And I can see you missed my huge sentence.
