So this was what Eldest boy wanted to play and he duly dug out his Eldar whilst small boy grabbed his Marines.
I set up a table, threw down three objectives and away they went.
VerdictTBH I preferred it to AoS - it was quicker (though the endless cross referencing and re-checking of conflicting special rules was wearingly familiar) and played as a series of small firefights rather than a huge bundle in the middle. I agreed with the boys that I'll help them work out a pair of 800 point forces and then we can play several games just with those so we all get a better handle on the rules.
I'm also going to get a copy of the current edition of the rules - not because I think they'll massively change things but just so eldest boy is actually playing the same game as his chums at school.