From the Sadoun site:
Dish: 1000+ 23.8”h x 30.9"w
Dish: 500+ 23.8”h x 30.9"w dish

I'd say the 24" wide dishes would outperform a regular Dish 500 (which is about 20" wide).
And the 31" wide dishes (78cm) would be as good or better than buying that 75. -

Of course, if you had a SuperDish, you could even use the bandstacked LNB it's got.

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