A tall stack headset can be thought of as a headset that has a "built in" spacer.
It is a tall stack because the dust cover is thicker than normal sized headsets.
This can be very helpful for making SCS fit correctly with the varying sizes of head tubes, forks, and clamps.
You can use tall stack headsets on most setups you would otherwise use a normal stack headset.
After the dust cover, everything else is pretty much the same.
You'll get the sealed headset bearings, wedge/pinch ring, and crown race included in all of the headsets you can find.