How pointless is this ship? Compared to a Brute it has +1 turret and +1 side/rear armour. This is pretty good and increases survivability against bombers considerably. However, it loses the 90° turn and also 2 dice when ramming and also costs 5 pts more. Given the Brute is a terrific escort because it has 90° turns, is really cheap and rolls 4d6 when ramming it seems that the Grunt is just a really really terrible Brute that performs a bit better against enemy bombers. That does not seem like a reason to take this ship.
So what about the other special rules? The traktor fields? Well, this is actually a downside, since it's not optional. The Brute could take it if you wanted to increase the chances of hitting an enemy. Of course, you could decide not to take it if you wanted to increase your density of Brutes. So this isn't a reason. So what about the BV of 2? Well, against a 2 turret escort this will mean that you'll give up only a +1 modifier to the opponent, instead of a +3. Against a 1 turret escort this will mean that you'll have the same BV, instead of giving up a +2 modifier. So that's a +2 swing, making it possible to board an escort. However, chances are reasonable that the in order to move into contact the Ork player has used AAF, thus cancelling the +1 Ork bonus to boarding. Hopefully the enemy escorts will be on orders, but there's no guarantee. Also, it's not terribly likely to have a BM in contact, since it'd be pretty hard to guarantee a single hit against an escort. Also, using a squadron of Grunts to take out a squadron of enemy escorts means there's almost zero chance of them all having a BM in contact.
So let's consider some Grunts boarding, say, some Cobras. Only 1 turret means equal BV. Cobras likely on RO (or BFI), and let's say the Orks are on AAF/BFI (due to ramming, so we're looking at the left over Grunts boarding the left over Cobras). So the Orks will get a +1 in boarding. That's it. That's pretty much best case scenario. We're not boarding Chaos or Space Marines or 2 turret ships here. Woot! +1 to the dice roll! Not only is this still a very risky proposition but even if you win, if you don't win by at least 3 then you'll still be destroyed on a 5+ (from the crit) and even if you do win by 3 or 4 there's still a 1 in 6 chance of being destroyed. And if you succeed you're risking a 30 pt ship to destroy a ... 30 pt ship! And what if the enemy has no escorts? You going to use Grunts against capital ships? If you're intending to ram/board you've got a pretty good chance of being destroyed by the ramming attempt and Brutes are much much better for this anyway. While boarding you'd need at least 4 to equal a damaged ships BV and yet again you have a strong chance of losing at least one escort even if you win. Given that the Grunt uses a large base I don't find it all that likely that you'll manage to get 4 of them into base contact with a small based enemy cruiser anyway.
So, for actual boarding, I really don't see the point. You risk too much and gain too little. For ramming, the Brute is better in every regard, getting twice the dice for 5/6 the price. That just leaves the option to take Klaws. These are good, but cost another 5 pts. Given that you have to move over a target to use them that means they're best used when ramming. So when ramming the Grunt will get 2d6 against armour and 2d6 hitting on 4's. A Brute would get 4d6 against armour (usually 5+) and cost 10 pts less. So for the price of 3 Grunts with Klaws (6d6@5+ & 6d6@4+) you could get 4 Brutes (+2 WB, 16d6@5+, 5pts cheaper). This comes out fairly clearly in favour of the Brutes.
So a really pretty pointless ship. To be at all worthwhile I think the Traktor fields should be optional, like it is for Brutes, and that they should count as BV 3 or 4.
