Berks do tend to be raspy and it's a bit of a Marmite thing, as far as I can gather the level of rasp depends on the exhaust you are adding them to, a true dual cat back may increase the rasp slightly but as Sipar has said you shouldn't have any trouble selling Berks here if you they are not for you. Changing anything on your exhaust yourself can be a complete ball ache, a lot will depend on how badly the original bolts are corroded, personally I wouldn't bother, get it into a local friendly mechanic/tyre place who has a ramp. Hope it all works out for you.