The Brothers of the Iron Fist barely saw the flying contraptions coming before they were already above them, with their Ork pilots cackling down with devilish glee.
The combat team's sergeant squinted, trying to get a better look at the attackers, and caught brief glimpses of deadly missiles and jagged buzzsaws, each more than capable of tearing through their power armor with little to no effort at all.
The sergeant reached for his pistol, but just as quickly, the thunderously loud flying machines had vanished, replaced by the dreaded sight of bomb-like objectives falling through the sky, headed straight down upon their entrenchment. The sergeant could do little besides brace for the impact, and pray to the Emperor for salvation.
The massive cascade of explosions rocked their fortification in a shocking, jarring rhythm, causing debri and shrapnel to fly around them in an exciting, if somewhat random fashion.
The sergeant waited a moment, to allow the smoke to clear, before addressing his second in command,
"What the hell was that?"
"We're not sure sir, some kind of fireworks display."
"Is anyone hurt?"
"No, just mildly inconvenienced."
"Oh...and they didn't fire their missiles?"
"No sir. We're not sure why."
The sergeant shook his head with disbelief. All that time and effort spent on speed and firepower, and they drop the equivalent of frag grenades on their heads...once. He just didn't get Orks.
Suddenly remembering himself, the sergeant glanced towards the sky, in the general direction he believed the Emperor to be.
Before I go any further, let me assure you that I use deffkoptas and I definitely like them, but only when they're fielded right. Unfortunately, the base cost of a unit of deffkoptas is already expensive by Ork standards, and most of their upgrades merely deepen their cost without adding much power to the unit.
With the release of the new Assault on Black Reach set, I bet everyone has at least 3-6 of these guys, and after a bit of testing, I've found the best unit size is a full 5. In a smaller game you could get away with smaller units, possibly even units of 1, but in standard play you'll want 5 simply because they can't take a bosspole. Their leadership of 7 gives them roughly a 58% chance of passing a panic check, which isn't great at all. Having 5 allows you to take a casualty before making that check, which definitely helps keep the unit alive.
Of all the fast attack options, Deffkoptas are perhaps the most vulnerable. With wounds instead of an armor rating, and no bosspole, they can be taken down by virtually any type of fire at all. Strength 8+ guns also cause instant death, denying them the advantage of their second wound. For this reason, I always outflank with the koptas. Not only will it keep them alive, but it also gets them behind the enemy, to fire at back armor.
So what should you be armed with when you get there? Not the KMB, that's for sure. It's their only gun option they have that isn't twin-linked, and with a BS of 2, you'll barely hit with it at all. Never take this option, ever.
I prefer big shootas, since they're cheap and can deal with back armor relatively effectively, but I've also enjoyed success with rokkits as well. It's not a cheap option, by any means, but an outflanking unit of 5 rokkit koptas can deal with virtually any sort of MEQ unit or vehicle (aside from a Monolith or Land Raider) the enemy can field.
All that leaves us are the other Deffkopta options.
Don't take them. None of them.
As you've probably guessed from the story, I feel big bombs are horribly overpriced. One shot, they always scatter, and they're no stronger than a frag grenade. Sure, they're random and fun, but unless you're fighitng hordes of genestealers, I can't see you ever getting your points back from them.
The buzzsaw is a favorite choice of many players, but the fact it's weilded by a regular Ork instead of a nob makes it a rip-off for its cost. It only has 3 attacks on the charge with strength 7, which is enough to probably kill a single marine, but not much else. Against vehicles, if we assume the enemy moved at least 1 inch, it'll only get 1.5 hits, and only 1 vehicle damage result. That may seem nice, but keep in mind that the volley of rokkits statistically inflict 2-3 vehicle damage results, and the assault of the 4 regular deffkoptas inflicted 1-2 glancing hits on their own. The koptas are good enough without adding the cost of a buzzsaw to the unit, and multiple buzzsaws is pure overkill.
VERDICT: 5 Deffkoptas with big shootas for 175 points, or with rokkits for 225 points, is a solid unit, worthy of a place in any Ork army, but only when no other options are taken. They're especially effective in horde armies, which need help reaching distant pieces of armor.
So go ahead and use the Koptas, but be sure to drop that buzzsaws and big bombs. Instead, why not use the points to add a unit of grots to the army?
Sure, the buzzsaw's cool and the bombs are fun, but grots win you games. The choice is yours. ^_^