I've been very tempted to get a heavy howitzer in my 1000pt list. It may be overkill in most situations, but nobody opponent would dare enter a building in it's line of sight. 3D6 hits! 3D6 with 4+ pen, no hard cover modifier or extra protection!! And if it scores 10 hits the building collapses and everyone dies without saves! And even if they do live, they get D6 pins. Plus its a 5 man squad so more survivable than many other gun teams, gets a gun shield, can get a spotter to indirect fire, and the SIG33 gun just looks cool.
I think I'd feel like a cheese master putting it on the table though. If not because it seems WAY overpowered, then because thematically it isn't likely that they rolled up this kinda gun for direct fire support very often.