I've tried a few combinations before arriving at what I have got now.
Larini sports cats, factory centre and factory rears, too quiet
Larini sports cats, factory centre and straight through rears, quite loud with a nice tone.
Larini sports cats, unsilenced X-pipe and straight through rears, barking mad. Very loud with a harsher tone but sounds fantastic when going for it.
Larini sports cats, lightly silenced X-pipe and straight through rears. Perfect. Lovely tone, quiet at low rpm/throttle opening but very loud when going for it and mega pops and bangs on the overrun.
Very happy with it now. For the time being!