While I was testing a repeater amplifier I was trying to use a Wouxun KG-UV6D V2 handheld radio to provide a 1 watt signal. I noticed that it overshot the output power to a great degree until it settled down to 1 watt output.

So, there are rigs that do overshoot power output and MIGHT be a problem when driving an amplifier.

73, Joe, K1ike