I think it all depends on the boost you run; My bro runs a Starlet GT Turbo on stock boost [around 10psi I think] and his cheap "no-name" BOV is actually louder than his mate's Blitz Supersound [also on a starlet running standard boost]

You might find a stock BOV is ok & pretty loud for now, but later you'll need to upgrade to something that can handle the pressure !