My red cube was under reading quite significantly when using the default calibration values, so much so that the fuel flow was registering as below the lower limit for the engine on takeoff (red cube between the servo and spider). It wasn't until a couple of flights that I was able to re-calibrate the red cube in the G3X, and sure enough the fuel flow is now smack bang in the middle of published range.
I wouldn't spend too much time beating it up on the ground glazing cylinders and risking stone chips. Just get it ready, ensure your baffles are as good as they possibly can be (go to town on the Permatex Ultra in any gap you can find between the AL baffles and the engine), go fly and keep that nose down on climbout (130kts) to ensure good cooling during the break in. I did my first oil change at 5hrs, a second at 25hrs then switched from break-in oil to W100+ at 50hrs and saw a 25degF drop in CHT (although unfortunately no speed gain). I did the first few hard running break-in flights using 100LL Avgas, then switched to BP 98RON mogas since.
IO-360M1B with dual PMAG