Yes, true. It all depends on what is under the covers to start with and what your expatiations are. There is no one answer, its all case by case.
I have replaced the gun and ground cables with larger gauges.
Added 200, 000 uF caps totaling 300,000 uF.
A second cooling fan.
Larger heat sinks with heat sink grease.
More drive to the Solid State relay.
I also prefer Hobart Fabshield Flux Core wire, the slag is a power that brushes off.
0.030, 0.035, 0.045 wire and the same for gas.
With the extra caps the arc is extremely stable, little or no weld spatter with FCW wire almost like spray arc.
Easily puts out 225 amps @ 40% duty cycle. Maxes at 300 Amps.