Alan,
There are quite a few people in the North east who sail cats and iceboats.
Once you sail iceboats a while you start to regard everything else as just soft water sailing.
DN plate runners are fine for your iceflyer. Have your friend teach you how to sharpen them correctly. Get a large sail. The iceflyer seems to be very slow unless it is windy. A big sail helps for the under 10 mph days. Don’t sail alone, and carry ice claws for safety

As far as top speeds go, A DN only goes about 60-65 mph tops.
Iceboats are at their most efficient in light wind conditions. In 5 mph of wind a DN goes upwind at about 15 mph and downwind at 25 mph. A skeeter which is a large, cool very aero iceboat will go about 20 mph upwind and about 40 mph downwind.

When it is blowing 20 mph a DN is going about 35 mph upwind and around 50-60 downwind a Skeeter is going around 50 upwind and around 85-90 downwind

These speeds are assuming “fast” ice ie smooth clear ice with no snow on it and good runners on a DN that you built in the garage with a bendy mast

When it is blowing 30 mph you get the hell off the ice and drink manly drinks like Irish whiskey and tell lies about how cool you are.

It makes my A cat feel like I am sailing in slow motion .

Eric Anderson DN US 5193