I've recently seen a lot of discussion about using Whirlwinds, and I was wondering if any had them actually perform better than Dev Squads with Heavy Bolters. For about the cost of three Whirlwinds, you can have two - six man Dev Squads with three Heavy Bolters a piece. You start on the board during escalation, while if you play escalation with Whirlwinds you only get, in the best case, 4 turns of shooting from the Whirlwinds, or 12 ordinance templates in a game, reduced from the maximum of 18 (assuming non-random game length). That's effectively removing a single Whirlwind from your offensive firepower. With scatter, and running up against MEQ and using mine-fields, I find that Heavy Bolters seem to kill more MEQ models than the strength six mines. The Heavy Bolters have a better chance to hit than the mine field, which offsets the worse chance to wound. Here's a quick rundown of my calculations: (assuming T4 target)
1 Heavy Bolter Shot:
2/3 chance to hit * 2/3 chance to wound = 4/9 wounds/shot
4/9 wounds/shot * 18 shots = 8 wounds (before saves)
1 Model Moving Through Mine-Field
1/2 chance to hit * 5/6 chance to wound = 5/12 wounds/model
5/12 wounds/model * 20 models = 8 + 1/3 wounds (before saves)
Obviously poor line of sight will seriously hamper the Dev Squad's effectiveness, while giving the Whirlwinds a better chance of eliminating return fire (i.e. hiding). But with 18 Heavy Bolter shots a turn (ideally), and 12 hitting on average, the three Whirlwinds need to get a significant number of hits to be similarly effective. If you are using the Vengeance Missiles, you need to get 12 hits, which after scatter and partials, seems difficult for me to ever accomplish, even with three pie-plates (it could just be that I scatter poorly, one of the reason that I love teleport homers). If you are using the Castellan Mine-Field, you need 20 models to walk through your mine-fields in a turn to be equally as effective as the Heavy Bolter shots.
Has anyone been able to use the Whirlwinds effectively in a tournament environment? Does their effectiveness warrant using all three HS FOC slots instead of two for the Devs? If you used them in a tournament or competitve games, do you feel that Heavy Bolter Devs could have done equally well?
Thoughts, comments, and any contructive response in general are greatly appreciated.