I am really keen to hear about this. After searching and finding this, I was initially upset that there were no replies, but then saw that the topic was created today. I'm using the rectangular, Australian equivalent called "Weetbix". As far as I know, they're more or less identical except for shape.
Do they have enzymes in them or a large percentage of starch that needs converting? I have 700 grams of wheat malt extract I'm prepared to use, and was hoping not to have to go to to the store for enzymes or base barley malt. I will be doing a 4gal batch, and am prepared to boost the OG with honey if need be.
Looking forward to seeing your recipe! I have no idea how to do one...