Not on a BX, but I run the G6 blades on my ZD mowers. They are the best blades I have ever used. Great cut, heavy duty, and they maintain the edge.
As far as G3,5,6 I believe G3 does not have the treated edge. Both G5 and G6 have the treated edge, with the G6 being slightly heavier duty overall (width and thickness).
I have the Oregon part numbers and buy them on Ebay. I did make the mistake of buying them by dimension once, and discovered the seller did not know how to measure mower blades so I would recommend going by oem part number.
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