Novarossi wants you to use a breakin bench and prop to break in their engines and it's hard to argue with such a successful company when it comes to what's best for their engines. That said, I've broken in many, many engines using both the blubbering rich idle a few tanks method as well as the bess (heat cycle) method. The blubbering method worked well back in the day, but with the tighter tolerences and more advanced alloys being used in todays race engines the bess method has proven to give me the most life from my engines. The average RTR or sport engine will pretty much need a few tanks at idle to loosen it up, but top of the line race engines don't need the pounding this method uses to reform the pinch area so the piston can pass it without getting stuck. A proper heat cycle insures even expansion and proper "seasoning" of engine parts which will result in optimum output over an extended service interval.