There is an issue I have always had with 40k stat lines and the ranged weapon rules Warhammer Community put up yesterday are basically the perfect illustration of it:
You see, I have basically no problem with any of that. I like how the lascannon is balanced to do a lot of damage to a single target (read: vehicles and their many, many wounds), I like how the flamer hits automatically on a random number of hits, I like the -3 armour save modifier on the heavy weapon.
The only sticking point for me is the boltgun and its complete lack of armour save modifier.
Now, a boltgun is basically a grenade launcher held by a man so big and strong that said grenade launcher has the same relative weight and utility as a rifle would to a normal human being. It fires huge bullets that embed in their target and explode.
And it doesn't affect the target's armour value purely because boltguns the most common “basic” weapons in the game. If you gave this gun an AP value under this particular system that would be hugely unbalancing to low armour factions like Imperial Guard and Orks.
Basically, because of how common they are, Space Marines kind of break the “realism” that game stats are meant to describe. Their basic guns should be incredibly devastating to armour, including Space Marine power armour, but it can't do that if the game is to have any hope of working. So I'm here ackowledging that these rules look well considered and balanced but I don't really think they describe the thing they're meant to.
Its not a huge issue because I'm used to it and the accompanying issue that the difference between a normal human's base stat of 3 and a Space Marine's base stat of 4 is so much bigger a representative difference than it is in Fantasy. Still, I had hoped that maybe this version of the game would take the clean break of totally invalidating all previous rules in one go and maybe the shift the stats a bit. At this point, the only way to do that after what we've seen would be to make Guardsmen pathetic and I really don't want that to happen.
Anyway, for the most part I'm still cautiously optimistic and I've been having a lot of fun making Flesh Tearers Vanguard which, hopefully, I'll have some pics of in the next couple days.