So just a small update on this one, official GW FAQ, gave two boosts to AFPs. The first is minor, barrage weapons determine which side of a vehicle they hit, depending on where the hole is closest. I thought it used to be, barrage was resolved against side armour? Anyways, just means that the st4 can potentially glance most vehicles rear armour. Makes taking the puretide chip not terrible I guess.
The other change, is barrage hits all levels. I've played it like this since the draft FAQ. I've had it used against me, and it makes typical terrain pieces like building ruins, into death traps. Even with armour saves, it just generates so many hits if you have a big footprint or multiple units in a terrain piece.