After the success of the OS GGT15 petrol/glow engine you would have been on a sure bet they would not stop there. This engine is the next in line and it is, like the 15, a winner. At 10 cc it is a good size for many models and certainly for multi engine aircraft. No fuss start a normal glow power supply does the job but be careful of power panels as some will kill the plug.
As an example of the testing, I recorded 9,974 RPM with an APC 13 x 6 propeller On a 14 x 4 I recorded 9,019 RPM.
Fuel was both Morgans Coolpower blue oil and also Deluxe Power Model oil with 95 RON petrol. The engine performed very well on both fuels and, as a side note, the exhaust efflux from the Deluxe oil was just a honey colour no black specks or black oil.
My full review will be in Australian AIRBORNE magazine # 263 and later in the UK magazine RCM&E