Interesting. I'm obviously gonna be in the minority here, but it's been my experience with Marklin that they are way over priced, don't run as well as say, Kato or Roco, and since they are 3 rail AC, you're kind of stuck having to use their products almost exclusively. A good business plan, I suppose, but not good for my tastes.
I got rid of mine, and replaced them with Roco for my few European items. They run on 2 rail DC, and are as smooth, quiet and powerful as any other brand I know of:
Having said all that, to each his own; if you like Marklin, then by all means I say "go for it"!
Mark in Oregon