Hopefully you'll have seen from my earlier post that I'm looking at putting together an Eldar army in the near future, and that it will be heavily leaning on the mobility of that race, specifically jetbikes, grav tanks etc, with those vehicles transporting some of the more aggressive units in the codex into combat. Now, with that in mind (and having watched a couple of reviews of the book on youtube from those people to whom GW have provided a copy) I had a bit of a think about jetbikes and their options. Here's the result of that, hope it sheds some light on things for you!
Ok, so first, we have three gun options for the windrider jetbike, the scatter laser, the shuriken cannon (or shrieker cannon if you're old like me) and the twin shuriken catapult.
In 7th edition the scatter laser was king, and scatpacks as they became known were the bane of gamers lives up and down the country Does that still hold true though?
Here are the number to back up why I think that the real winner these days is the humble twin shuriken catapult! I have a few thoughts on points costs but as I don't have the book in front of me I'm not going into too much detail on that one yet. All the analysis is done on a 10-man unit size (which might not be available, but you get the idea) so that it represents a good sized unit and gives us sensible numbers to work with, and assumes that the unit is within optimum shooting range (I'll come to that later).
Assault 3, S6, 1 damage, 24" range and no AP (unless you roll a 6 to wound).
So, a 10 model unit puts out 30 shots, and given its damage and armour penetration characteristics is clearly aimed at taking down mainly infantry targets.
Against T3 targets, 16.7 wounds before saves
T4 - 13.3 wounds
T5 - 13.3 wounds
T6 - 10 wounds
T7 - 6.7 wounds
T8 - 6.7 wounds
Now the first thing to notice here is the new wounding chart makes an impact, and with no T12 units out there (yet) we don't need to worry about only wounding on 6's. These figures take account of wounds caused before saves so that you can then factor in an armour save against a particular unit irrespective of toughness. Of course we also need to factor in that on average, 1 of every 6 wounds caused will be -3AP.
Heavy 4, S6, 1 damage, 36" range and no AP
Our 10 model unit is now putting out 40 shots (and won't suffer penalties to hit because I'm using Saim Hann attributes for these calcs)
T3 - 22.2 wounds
T4 - 17.7 wounds
T5 - 17.7 wounds
T6 - 13.3 wounds
T7 - 8.9 wounds
T8 - 8.9 wounds
So here we see the same impact from the wounding table as with the shrieker cannon, but all the numbers jump higher because of the extra shots. However, looking in a little more detail, for example against terminators, the scatter laser is only likely to cause 3 wounds, whereas the shrieker cannon thanks to its occasional AP boost, has very good odds of doing 4 wounds, and effectively taking out an extra guy. Of course, the worse the save of the target the less significant that effect and the more efficient the scatter laser becomes.
Twin Shuriken catapults
Assault 4, S4, 1 damage, 12" range and no AP
Again, we have 40 shots from our 10 model unit, but this time they're only S4. Prime targets are still the same though, infantry (more so you'd think than the other two weapons, but let's see shall we?)
T3 - 17.7 wounds
T4 - 13.3 wounds
T5 - 8.9 wounds
T6 - 8.9 wounds
T7 - 8.9 wounds
T8 - 4.4 wounds
Right, so here's where the wounding table really kicks out an odd result! Have a look at the T7 figure, and compare it to that for the Shrieker Cannon...
Because of the way wounding works now, both the Shrieker and the Twin Catapult wound T7 models on a 5+, but the extra shot per model from the catapult variant means that you'll get more bang for your buck shooting at these guys than you would with the shrieker cannon, despite its extra strength. So in fact, shooting at vehicles with twin shuriken catapults is more effective than with a shrieker cannon (not that I'd recommend you use either for a job like this!)
So, looking at those number, and taking only those numbers into account, the scatter laser still looks a good bet for an all-round list, because of the extra range, extra shot and higher strength giving it the advantage. It's also better for the same reasons against more lightly armed opponents, whilst the shuriken cannon and catapults perform better against armoured targets (though the catapult performance drops off against T5 armoured units, there aren't too many of those around).
There's more to it though, because obviously I've not yet touched on the range differences at all. Scatter Lasers are clearly the winner here, allowing you to stay far away from your target and any reprisal, with catapults being the least attractive option in that respect. However, there's (once again) more to it than that, because we haven't factored in cost. And I don't yet have the final costs of the weapons, though I'm fully expecting the twin catapult to be cheaper than the other options (it was in the index).
Now, add to that the fact that jetbike movement is insane, the catapults have an effective range of 16" (movement) + 6" (advance) + 12" (gun range) to give them a total of 34", which will reach out and touch most units on turn 1, and I'm pretty satisfied with thinking that not only can I be nice and 'fluffy' by taking bikes with shuriken catapults, they're also actually a very competitive option when you compare them to the alternatives.
Windrider jetbikes are just as fast as they ever were, and although they now don't come in the troops slot, they are still a great choice if you want a mobile choice that can mow down light infantry with abandon. They won't take out vehicles for you, but they were never supposed to anyway, 7th just happened to make that a thing for a while.
If you want to be told which is the best weapon option for them? Simply put, there isn't one. Scatter lasers still look very strong (assuming you're using Saim Hann attributes), but are likely to be more expensive than the alternatives, bringing their efficiency back down to comparable levels.
I think I'll be taking two big packs of these guys, with twin shuriken catapults and pushing them down my opponent's throat with some wave serpents carrying some other nasty surprises. Gunlines beware, there won't be any time to reload against this army!