catalytic converter failing/buzzing

[bluesmoker]

suggestions?

my mechanic says the entire down pipe including the cat must be replaced but only the cat is failing (internally the substrate has broken free)

any opinions on having a muffler shop cut out the cat and replace it with this,

http://www.tdotperformance.ca/magna...YSFi-P5tHbR3odZI0DmXLyFltAXmkjSVutBoCkpXw_wcB

a 2 inch inlet/outlet would fit my 2004 bew right?


thanks