The build quality and sound brilliant, you can control the sound by a switch to make it louder or quiet, you wouldn't go wrong with this. The only thing you have to consider is whether you want a titanium or stainless, they only build the exhaust in stainless also the price is pretty expensive. cheers
I've heard the Kreisseg Valvetronic F1 exhaust system on a Gallardo Superleggera and a Lotus Exige S and both sounded fantastic! They are pretty expensive but of good quality. The wireless remote feature to turn on/off the valve is great depending on whether you're in the mood.