Fixed wing pilot here.
The way we are trained is that even though the engine is on fire its still producing power so better to use the performance to get away from the ground and get some speed on then shut it down.
500ft is our nominal acceleration altitude away from V2 to Vyse this does vary with aircraft type and also local terrain performance.
Sorry to join in if I am not welcome I saw the thread on the main page and although we practise it in the sim etc and its interesting to see the way the rotary world deal with it.