i fly a PA34-220T (IV) which is indeed rated for 220 hp for 5 minutes.
I don't want to put too much unnecessary stress on the engines, so I always take off with full power and retard to climbing power after gear up at between 300 and 400 feet, obviously above blue line speed (at least 100 IAS), a level which i feel will give me sufficient height in case of a sudden engine failure.
As with all engines, retarding to climb power needs to done in a smooth way
In effect i therefore do not use more than 1 minute of full power