I've used ATLAS track + switches over the past 20 years for two major layouts. Great track - and more quiet and effortless as any other.
On the second layout, now four years old, I dumped the Atlas switch machines and used Z-Stuff. I'm happy.
Having stated that, though, if I were beginning again right now with no track, I would use Ross. It's almost as solid as Atlas and almost as quiet ... but it's cheaper and AVAILABLE (and the switches seem to be better). So, there's no question: Ross right now.