For what 3 rail O gauge scale can be-check out what Norm C. does. To me, that is the ultimate O gauge layout. there are others out there, too, I am sure.
While it is possible for any given model (of anything at all) to be very close to scale, all model railroads are a caricature of the prototype. The most fanatical fine-scaler still uses curves sharper than any prototype and the largest model empire still has no more than a few scale miles of track. It always comes back to different-strokes-for-different-folks or whatever-floats-your-boat. That is, is it fun?
Personally I am of the Frank Ellison school in viewing the layout as a stage and the rolling stock as the actors in a play that I put on. Operation is my thing and I stick with bullet-proof truck-mounted "lobster claws", oversized flanges and the third rail for the sake of near-100% coupling/uncoupling performance, zero derailments and 100% no-stall electrical performance.
I use Lionel near-scale NW2s, near-scale F3s, near scale extruded aluminum passenger cars, and MTH near-scale freight rolling stock rolling along on semi-realistic Fastrack through semi-realistic scenery. To my eye and brain this stuff looks and acts like real trains in miniature. I have watched more than a few prototype coupling/uncoupling operations and the lobster-claws are large enough to visibly evoke the real thing in my brain. When I look at the oversized flanges and 5' gauge in my mind I see the real thing. Again, to me it is all caricature and mind games and it is fun.
As such I do enjoy the 3rs forum but probably have nothing to contribute there.
I must be a 3-rail scale person, too although my third rail is about 4½ inches above the center of the track!