Honestly I don't know the sq.ft of that chute and I have not used it for a while. It was one of the chutes Hans used in the W 1000. It will sheet to the rear beam so I know it's not small. I'm using one I got from Robbie D. off his T.

The T's and the M6.0XL are close in dimensions,board type so having Robbie local is good for used stuff. One thing about T chutes is they are designed to go downwind and may not be flat enough to reach up like a N20.