My regular opponent, Shaun, and I used to play 40K campaign battles three or four times a month but all this ended with the advent of the turgid 6th edition.
The Mighty Eighth has reawoken our interest so we set up a simple test game of my Alpha Legion versus Primaris Marines in a straight forward shoot out at the Gothic Corral. Shaun's standard smurfs stood in for the Primaris.
First thoughts are:
It plays smoothly and is very Siegmarine, aka Age of Sigmar, but the running order of the turn phases is different and measurement is base to base.
The only core 'special rules' are one rule for each weapon type - i.e. pistol, heavy, assault etc.
You can't shoot into a melee or while within a melee, otherwise you can freely target almost anything within line of sight.
Base to base measuring and no melee ranges (other than two bases deep) makes the close combat system much smoother than AoS.
Heroes are back; a Smurf captain took out a whole unit of chaos cultists single handed.
The game ended after three turns and the result is shown above. A Primaris tactical team and two units of cultists had been taken out and the Helbrute was on its last legs. From our experience with AoS it seemed likely whoever won the initiative would win the game so we just rolled for it. The Smurfs won and so were awarded victory, probably fairly.
Overall: Good fun.