Nice gurgle noise from exhaust but is it good or bad. Help?

[Zac1412]

Hi folks, my evo 8 running 380bhp ish with usual mods makes a nice gargling noise from the exhaust, but is it good or bad. If I am going down a slight hill in 2nd or 3rd gear and the engine is very lightly engine breaking the gargle is not there... Until I touch the throttle so lightly and I mean lightly (around 2mm on the pedal) the rev counter doesn't even notice the change and the car goes goes no faster . However then it sounds much deeper, gurgles and sounds awsome!

Why does it do this?
Is it good or bad?

Thanks