I also used AM track a mix of the R27 curves, straight sections and flex. The complaint is their track is brass rather than nickel silver but I'm pleased and so are others.
AM track may be brass, but it held up very well with the modular group I used to belong to. Whatever alloy AM is using, it's different than the HO brass track of olden days.
While I would run a track cleaning car around after set-up, that was mainly to compensate for the various members storage conditions. Otherwise, we could run 8-9 hours straight during a show without ever having to clean the track. And if it was a two day show, didn't have to clean on the second day, either.