My experience is with old pratts and curtiss wrights.
Cranking the thing thru so many blades to clear the oil and lower the risk of blowing the heads off then tickling the primer balancing the throttles and the ignition.Been many many years but it was an art form to get them started without stalling it, over priming, under priming ignition to early blam fart bang crash ...The risk of fire was pretty high too!
I guess it is mainly the oil issue with dirty plugs.They sound a bit clunky until the boost kicks in too. cant beat the sound of big piston engines when going full noise.