[whirlyspud]

I flew all season last year without it. I added it this winter for one reason, and that was to strengthen the cowl. Mine was starting to crack a little. Even if you don't want to use it, I would still cut the outside ring out of it and use that to beef up the cowl a little.

Edit. For cooling, I cut out the covering on the bottom of the fuselage between the landing gear and the cowl.

Mike