plank to egg whisk
I did fixed wing conversion to helicopter 5 years ago after 10 years fixed wing. The main reason was the added convenience of going from home direct to my destination. I still fly fixed wing too and do 150h/yr helo vs 125 hr/yr F/W.
Most important thing you need to learn when converting from FW is how to hold the thing in a stable hover and then you are away.
Trying to learn RT, navigation and airport etiquette at the same time (ab initio PPL(H)) would have been far harder.
So IMHO, fixed wing helped me as background, just remember which type of aircraft you are in at any particular time and whatever you do don't suddenly push the cyclic forward!
An aeroplane is a flying machine, a helicopter is a machine that flies!
SB