BMW 4.6 is poor acceleration and hesitation

[Aman]

Originally Posted by sethhatfield

It's the catalytic converters are clogged and broken apart inside their shells. I had the same problem and had mine replaced with a pair of universals for $364 and I got all the power back. I wouldn't rev past 4000 rpm when flooring it. The muffler guy cut them off and chunks of crap fell out of them.

Thanks for your input.
Did you have the rattle like the one in my video on page 2?
Do you have a 4.6 too?
What made you suspect the cats rather than coils etc?
Many thanks for your help