Cupcar confirms in post #23 what I mentioned
main bearing alternative
I'm not sure what you mean by opening the box and finding randomly colored bearings. All of the Glyco OE and OEM STD 911 (regular, old 911, not actual GT3) main and rod bearings I've handled have no color markings on them.
I don't think you'll find info here that the OEM aftermarket (non Porsche dealer boxed) Glycos are consistently tight. What you'll find is that they are becoming more and more inconsistent in terms of visual quality and measurable quality in terms of consistent clearance results from journal to journal, assuming all crank journals and case bores are consistent.
As far as obtaining those red & blue marked bearings. Not an easy task. Porsche Motorsport doesn't sell those to just anybody.