For a track bike no Fan is okay because you don't stand still much but I would be careful with a road bike. Radiator needs airflow to work usefully.

Your absolutely correct radiators don't work if no air is passing through them.

Which is why, as a road bike which has had the fan removed and will therefore get hot if stationary, I'm thinking of using this type of coolant.

Are there any other NC30 owners who have this coolant in their bikes?

I have no working fan on my NC24 as well at the moment. As long as I'm not stopped at a traffic light for not much longer than about 5mins the temp is fine. Any longer and I turn the bike off to be safe. I use 500ml of WYNNs Chilly Willy coolant/antifreeze and have no hassles. Being in South Africa with 30deg+C temps and ho overheating issues yet.