Enough time for a sightseeing visit?
I suspect when you get off the ferry at TST you'll find that the locals will tell you there's enough time for them to make you an entire suit!
Hong Kong's a fantastic city - the only thing I'd add to the earlier advice, purely if you fancy a bit of nightlife, is to head towards Lan Kwai Fong (a little way over from Central) for a drink/meal.