How clean and well layout obviously do not determine the final SN and cross talk scores, but it surely shouldn't hurt. Being curious, I checked my list of 63 AVRs bench tested by S&V and sorted them by SN and XT. The results are:
Of the 63 tested by S&V/HT(before the merge), 51 had measurements for both XT and SN.
Sort by SN, the top 10 are:
AVR-4810CI, AVR-4310CI, AVR-2311CI, SR6006, AVR-X3400H, AVR-5308CI, CXR120, TX-RZ610, MRX1120,RX-A1010
Sort by XT:
AVR-5308CI, AVR-X7200W, AVR-X5200W, TX-RZ610, DTR-8.8, TX-SR805, STR-DN1060, AVR-4310CI, DTR-9.9, TX-NR5008
Sort by SN, then XT, and expand the list to include the top 15 of the 51 units tested:
Now there is one NAD, the T747 in the 12 th place, the Denon AVR-3312CI squeezed into the 11th place, and the entry level Denon AVR-1913 got the 13 th place, followed by the AVR-X7200W in 14th. The difference in SN between the 10th and 15th were in the second decimal point (i.e. less than 1 dB).
I am going to do the same using the AH bench test results. It will take a while because Gene's bench tests involved more metrics and more specifics about the test conditions. It's going to be a time consuming exercise.