Robert in Texas conducted this interesting experiment during VOA Radiogram, 4 May 2014, 1930-2000 UTC, 15670 kHz:

I received the Sun 1930-2000 15670 kHz broadcast 4 times simultaneously with the exact same radio, antenna, and settings with the exception of mode. I had 4 receive slices set up in the radio on the 15.670 MHz on AM, Synchronous AM, LSB, and USB. See the picture for the results.

The text was generally received 100% with a few errors in the LSB and USB. Also on LSB and USB I had to set offsets off of 1500 (1472 for LSB and 1531 for USB) before the text would decode properly.