Given it's been... six months since I said this and all of my effi testing has been postponed indefinitely, I thought I should at least share my binning results from earlier this year.
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For those who just want the raw data, I have a spreadsheet here. I have screens for (almost) all results here.
Tested on Maximus VII Impact with binned 4790K. Note 2.39V VDIMM cap for 1400MHz CL8 testing in particular.
Sample size: 148 sticks, all JEDEC 1333 9-9-9 1.5V rated. Composed of 121x SR (73x Samsung M378B2873GB0-CH9 and 48x Transcend TS128MLK64V3U) and 27x DR (14x Samsung M378B5673GB0-CH9, 13x Samsung M391B5673GB0-CH9).
Four tests were used: 1333MHz CL8, 1400MHz CL9, 1400MHz CL8, 1466MHz CL9. At each combination, tightest tRCD and tRP at "any" voltage were found first; voltage was then minimized for these tight settings. Binning recommendations based on these tests:
Ability to run 1333MHz 8-11-12 at any voltage (est. top 20% stick). Among sticks that can do these timings, above average sticks can do <2.15V.
Voltage for 1400MHz 9-12-13: <2.00V is above average, <1.95V is potentially interesting, and <1.90V is strong (top 10% on this matter). This is good as an easy test, but not as a one-stop binning procedure.
Ability to run 1400MHz 8-12-12 at any voltage (est. top 5% stick). If just looking at CL8 scaling, ability to run 8-12-13.
Ability to run 1466MHz 9-12-14 or 9-13-13 with tRFC88. Among sticks that can do these timings, above average sticks can do <2.10V. Top tier sticks (top 2-3%?) can do 1466MHz+ 9-12-13.
On average, compared to Samsung SR OEM, my Transcend SR OEM sticks seemed to have worse tRFC and tRP scaling, but better tRCD scaling. There's too many factors to point to one specific reason for this -- could be manufacturer binning, PCB, just an artifact of sampling, etc.
My luck with Samsung DR OEM non-ECC was very bad, with only about 50% capable of 1400MHz 9-12-13 at all, and a few sticks with subtiming weaknesses.
Samsung ECC PCB (M391B5273DH3) does not seem desirable for OC, due to a 1400-1414MHz clockwall and need for +1 RTL versus non-ECC (but RTL binning can help).
For anybody interested in an even more granular breakdown:
I'd be very curious to see results at this scale for DR sticks, if possible; unfortunately I had a much harder time finding them in large quantities or for reasonable prices versus SR sticks.