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This was an interesting conversion idea I saw on another forum on that tau website (forget what it's called)
Basically, take BR deffkoptas, cut off the landing skids, tail fins, rokkits, and the whole propeller assembly, and put a pair of wheels on the bottom, scratch-build some dakkaguns out of shootas, etc, and call them bikes. I've considered doing this, but i kind of like the Roflkoptas. In my list (see 1500 Goldteef's Boyz), the only long-range anti tank I have is 3 rokkit buggies, and I think they could use some support with the Roflkoptas (7 twin linked rokkits should do SOMETHING).
So: should I keep the 4 Roflkoptas I have (4 twin linked rokkits, 2 big bomms, 1 buzzsaw), or convert them to 3 biker boyz and a PK biker nob?
Well, the unit choice is up to you.
3 Biker Boyz and a Nob would be sweet. I actually would love to see how they did that, because I have 4x Koptas I might convert if it's not Terribley difficult.
As for converting...well look at it this way.
You can easily replace the AOBR Deffkoptas by either buying them cheap offa Ebay or getting another set of AOBR. (usually Deffkoptas go for $10-$15 for the squad of 3). However, you can also get some cheap older OOP Warbikes off Ebay. You could probably pick up 3-4 for around $20.
If these AREN'T AOBR Deffkoptas, I would keep them as they are. If they ARE the AOBR koptas, you could replace them...or just buy cheap Warbikes off Ebay.
Both can be useful, but they have different uses. Bikes are a LOT better in close combat, since they can take a nob and a bosspole. They're just as fast and more cost effective, all things considered. On the other hand, deffkoptas can outflank, and their big shootas have much better range (I don't use rokkits on koptas, they're too expensive that way).
In either case, I wouldn't use less than 5 in each unit, and 6 is really the sweet spot for bikes. I'd just use whichever you like using better, but in general, I've found that bikes are better in speed freaks armies (with lots of trukks and battlewagons), and deffkoptas are better in footslogging hordes (multiple units of 20-30 boyz). This is because you want the bikes or deffkoptas to reach the enemy the same time the rest of your force does. Bikes are much faster than a horde, so your opponent would just focus on the bikes and shoot them to death long before the rest of your forces get close. Deffkoptas don't work in speed freaks because if they show up on turn 3 or 4, then you won't get them when you really need them, which is when your trukks reach the enemy front lines.
"Any job worth doing, is worth doing with a powerklaw."
This has definetly helped. I have 4 mobs of 20 and a mo of 10 kommandos, and I think that the roflkopters would be better suited. I really want to keep the rokkits on though, because I want that extra punch gainst vehicles.
So my next question: rokkits or big shootas? The squad of 4 also has 2 big bomms and a buzzsaw, so I want to dedicate to either anti-infantry or anti-armour, and
nevermind, I just answered my own question. Big shootas it is.