No offence mate, but most here would rather have reduced noise, not more. Cheap crappy after market exhausts and cats have generated loads of complaints from us abouts noise. Drives you mad after not very long at all. It sounds to me like you've got the original setup so my advice is look after it and don't mess with it. There's nothing cool about a chaved up Mig (or a chaved up Corsa for that matter)
IMO people who consider anyone who drives a loud car to be chav is a seriously narrow minded individual who has to learn how to have their own opinion and not have there life led by the media. in other words get a life!

Have you ever heard the saying "if its to loud your too old"?

My omega is as loud as all hell! (im not a "chav" just not a OAP either!) the previous owner has completely removed the bottom part of the airbox and cable tied / taped the filter on, never caused me any problems and makes changing the filter really easy lol.
On idle and light throttle there isnt much diffrence, but when the pedal hits the floor it roars like a beast!
And yes i am more than aware that it will suck in warm air when the car is standing still, but how often do you need full power from a standstill? it will lose some low end torque but gain some high end horses, which suits my driving style.