[Milsurplus] 102E receiver comparison GRC-9

[Hue Miller]

Current 'Electric Radio' has article on China 102E receiver.
Sez stability of both HFO and BFO are superior to GRC-9.
Why is this, anyone?
I also see an article on a BC-106, GRC-9, 102E power supply,
that instructs to adjust GRC-9 xmtr filament to 6.6 volt.
Since the tube operates perfectly well at 6  volt, isn't this a
longevity hazard to the scarce 2E22 bottle?
Also the HV supply seems to depend a whole lot on capacitor
charging toward peak. It uses a 750 vct xfmr with fullwave
2-diodes with capacitive input. I suppose that would put it up
around 450 volts D.C.    I would have used a  550-600 volt
xfmr in a 4 diode bridge. Old school.
If the GRC-9 second IF was a 1L4 instead of the 1R5 IF/
BFO dualpurpose, would the IF section have greater gain?
-Hue Miller