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I don't, but I have it on a Micro Engineering girder bridge. It looks fine, and if assembled properly, and if you use NMRA RP-25 conforming wheels, you should be fine. Just take pains to clear grains of ballast off the ties and the webbing of the rails before you glue your ballast. Otherwise, your trains will bump and be noisy.
All my mainline and turnouts are code 70. Some of it hand laid and the rest of it Micro Engineering. It does, as mentioned above, takes pains to clear grains of ballast off the ties and the webbing of the rails before you glue your ballast, but is worth it as you can see in the hopper shot though the odd grain gets into the webbing.
My hidden areas are Atlas and Peco. Most sidings are code 55.
...from this, and other forums, that lots of folks are using code 70, and that it's even very close to prototypical for my RR and era. I have acquired 198' of ME rail and enough CVT tie strips to handlay. Also CVT #7 and #9 turnout kits. I'm going to try the Proto87 frog kits with them also.
Now to start doing some benchwork. Will be in 20' X 12' room around the walls with duckunder.