I have standardized on Peco switches (I like there positive locking, they don't need a switch machine to work), but I use both Atlas and Peco flex track and even some Atlas sectional track. I use Code 80 for main lines and usually use Peco Code 55 for sidings and spurs.
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.