I tested a prototype at the weekend and was very impressed. My engine is not normally up to temperature for my races as I am involved in race control now and to know that the engine can get up to temp before starting it is great. After doing the BRCA National at Ware where you are not allowed to start your engine before the final I can see it being a great help. Also to be able to heat up new engines to run them in is going to be fantastic. Tried this on a new Sirio at the weekend and it helped alot. A friend at my club is now making these.