Some extra information gathered after the main review:
1. Low power issue
Some readers suggested that the MOS FET used for 10 / 6 meters is not up to the task. After checking Mitsubishi’s factory specs this assumption seemed plausible at first.
Decoding Mitsubishi Si MOS FET model numbers:
Mitsubishi RD70HVF1 Specifications:
In the end the assumption proved to be wrong; the Yaesu FT-8900R uses exactly the same Si MOS FETs for these bands. This leaves a design error, a bad MOS FET, or an unknown problem with just my review sample.
2. Squelch levels
Good news: these levels actually mean something.
Bad news: even a noisy signal equals full deflection.