I'll second 8out
You only need to fly abroad a couple times, to truely know ow controllers make the skies of the U.S a luxerious place to fly at.
In my country to practice a stupid ILS (that is available in only one airport) you have to schedule in advance and sometimes they cancel that clearance in when you're in the air, inbound, while being vectored for the ILS on the basis of traffic. Or atleast those were the old laws.... now days they have ceased letting people practice ILSes at that airport, it's only sim or flying internationally to some other place..... fun huh?