According to Toshiba the 2sc2290 is a 60 watt transistor without harmonics. I'm sure lots of people see 200 watts out of a 2290 with 10 percent of that power on the fundamental frequency.
One thing to keep in mind, is that those spec sheets were written with a 12v reference voltage. Now, no one runs their amp or radios @12v. Most run them @13.8v or higher. When keyed, that voltage will drop according to the quality of the power supply - be it a vehicle's electrical system or the AC to DC supply. Think it is fair to say 70 watts @ 14.1v isn't much of a stretch with a stout supply.
I agree with you about amp mfrs will give watt ratings with no consideration at all as to the cleaniness of the output. An 8 pill 2290 amp with decent biasing (al la Texas Star) @14.1v (voltage drop estimate) should put out ~560 watts with a clean input source. But who considers having a clean signal? Yes; any operator that has been around awhile at this sort of thing - should certainly know better than being satisfied with over-driving the amp! I prefer to put out 120 watts of clean output rather than 240 watts of nasty harmonics and a crappy sound when transmitting. But that - is me . . .
:mellow: