If the second 2133C8 kit is also owned by Allen's Avantium that fail 1200 8-10-7 on air (which is very likely) then BBSE binning becomes a clear issue. If you start looking for bad air kits then you'll end up with stuff that fails 1066 9-9-9 and I bet is equally bad cold. And testing each kit on LN2 is not very practical from time/money/resale viewpoint.

All hopes now on PSC at being more consistent...