When I first heard the rumored rules about the various Kill-Team formations in the DW Codex, I was a bit discouraged (as many other players currently are, I think) because of the requirement for every team to have a squad of DW Veterans plus a Librarian/Terminator squad/VV squad/Biker squad combined into an unwieldy “super unit” per the Kill Team special rule. The fact that, outside of a CAD, Bikers and VVs can’t use their superior mobility because they are “tied-into” a unit with foot-slogging Veterans was one big hit against the Kill Teams. Another mark against them is that, if they include a single Terminator, Biker, or Vanguard Vet, then the entire unit cannot ride in a Rhino or Razorback; also, if the unit includes a Vanguard Vet or Biker, then it cannot ride in a Drop Pod or Land Raider (any variant). Finally, the Terminators in a unit lose their ability to DS because the rest of the unit does not have this ability.
Looking at all that, it would seem that the Kill Teams, despite their strong bonuses against selected enemy unit types, are almost irreparably crippled. On closer examination of the Black Spear Strike Force (i.e. the Deathwatch “Decurion”), I think the Kill Team formations might actually be better than I initially thought. First, let’s look at the Black Spear Strike Force overarching rules:
 Veteran Master of the Watch – WL drawn from this detachment may reroll results on the DW WL Traits table –A decent little bonus, but not the main “ummphh” of the detachment.
 Flexible Mission Tactics – Allow you to change the Mission Tactics one additional time per game (so two times a game normally, three times if you also have Watch Master as your WL, and a max of four times if he has the vigilance Incarnate WL Trait)– Quite a solid ability here, and one that I think savvy DW Commanders will put to excellent use.
 – Sudden Onslaught — All non-vehicle units in the detachment gain Deep Strike (yes, this applies to Bikes too) — Now, this is the key, since it means that, no matter what their composition, Kill Teams within the Black Spear Strike Force can DS without needing to ride in a Drop Pod (which Bikes and Jump Infantry cannot ride in anyway). This, along with the Corvus Blackstar’s ability to carry Bike and Jump models, gives the Kill Teams access to essential mobility.
So, taking all this together and looking at what “composite” Kill Teams consist of, I think we start to see another picture. For example, if a Kill Team includes even just one VV model, then the whole unit gains Heroic Intervention (i.e. ignore Disordered Charges and re-roll failed charges), which is a pretty amazing ability, especially given all the different close combat options at a Kill Team’s disposal. Similarly, if a Kill Team has just one DW Bike, then the whole unit gains Split Fire, Skilled Rider (so ignoring Dangerous Terrain, which is GREAT for DSing), and the ability to have the Biker “tank” for the unit against AP3/2/1 attacks with his 3+ Jink save. Finally, if only one DW Terminator is part of the Kill Team, then the whole squad gains Fearless, which isn’t essential (given ATSKNF), but can be tremendous for making sure you precious units do exactly what you want them to do both in and out of combat.
Another thing to look at is that, even though the entire unit cannot move 12″ because of the Veterans and any Terminators included, the Bike and Jump Pack equipped models can still move up to 12″ individually, as long as they maintain coherency with the squad by “conga-lining” back to the rest of the unit. This allows for longer “reach” when trying to get objectives, set up charges, draw LOS for shooting, etc. While this is no where near as simple as using mono-type units that can all move the same distance, in skilled hands I think it can actually be surprisingly capable on the table-top.
Now, on to the actual Kill Teams:
 AQUILA KILL TEAM — 1 Veteran squad and 1 or more selected from Librarian/ Terminators/Bikers/Vanguard:
***The Aquila is the “generalist” Kill Team, with re-rolls of 1s to Wound/Penetrate against ANY enemies by its non-vehicle members. This is quite exceptional, since every turn they can apply their remarkable combat power against whatever enemy you choose and still get a bonus to their To Wound/To Penetrate probabilities. An example “build” for the Aquila is 2 Terminators with Chainfists and CMLs and 5 Veterans with 4 Frag Cannons, plus the 5th model upgraded to a Black Shield with PF/LC combo. The entire unit can Deep Strike in (or ride a Drop Pod, Land Raider, or Blackstar), Terminators provide Fearless, tanking with their 2+/5++ armor, and 4 x Missiles a turn (plus Chainfists to threaten vehicles) while the Veterans provide anti-MEQ up to 24″, anti TEQ at 12″, and anti-horde at Template range with their Frag Cannons. Finally, the Black Shield has either 4 x LC or 4 x PF attacks on the charge, which doubles to 8 attacks of either of these if the Kill Team gets into combat with a MC, an IC, a Vehicle, or if the unit is outnumbered. Combine all that with re-rolls of 1s to Wound and Mission Tactics and you have a genuinely dangerous, versatile unit that can handle many different situations.
 VENATOR KILL TEAM — 1 Veteran squad, 1 Biker squad of at least two models, and any number of units from Librarian/Terminators/Vanguard squads:
***The Venator is the “anti-Fast Attack” Kill Team, giving all of its non-vehicle members re-rolls to ANY failed To Wound/To Penetrate rolls against enemy Fast Attack type units. Obviously, this is very effective against armies that typically field lots of highly mobile choices (Dark Eldar, Blood Angels, Necrons, White Scar Marines, KDK, and Eldar all immediately come to mind). An example of a Venator Kill Team build is 5 Bikers with Power Lances and 5 Veterans with 4 x Infernus Heavy Bolters and 1 Black Shield with PF/LC. Deep Strike the unit behind enemy lines and unload with 10 Special Ammunition shots of your choice and either 4 x Heavy Flamer Templates or 12 x Heavy Bolter Shots that also re-roll to Wound/to Penetrate against Fast Attack type units. When the enemy shoots back, use the 3++ Jinks of Bikers and majority T5 for the unit to tank wounds, then next turn you can shoot again with Biker’s Bolters and the Veterans Infernus Bolters and charge with the whole unit, mopping up whatever is left with 15 x S5 AP3 Power Lance attacks, 12 x S4 AP- attacks from the Vets, and 4-8 LC or PF attacks from the Black Shield (NOTE: If you are charged yourself, use the 4 x D3 Wall of Fire auto-hits from the Infernus Heavy Bolters and the TLed Bolters from the Bikes to inflict a surprising amount of wounds in Overwatch, especially if the enemy has a 4+ armor save or worse). Remember, with the “Venator Tactics” Mission Tactic activated, you get to re-roll ALL 1s to hit, both for shooting and assault, as well as all To Wound/To Penetrate (again applying to both shooting and combat) against Fast Attack units… imagine this against a potent enemy Fast Attack choice like Canoptek Wraiths… even without an attached HQ, this Kill Team averages 10 unsaved wounds against Wraiths if they shoot and charge them on the same turn, for example, using the Venator Tactic and Venator Doctrine.