Gotta tell you, this thing is awesome. I have a 7yr old Joe, and originally just wanted new side tables (also nice upgrades). But this basket is a game changer. 

It definitely helps regulate airflow by keeping the coals off the air holes.  The best is the next cook. Just lift it up and sift out all the ash. 

Warning:  it comes with a coal divider (haven’t used) so now I’ll probably buy some half moon plates for better zone management.