Ignoring kits that are no longer available, you can now get a multi-melta in the Space Wolf Dreadnought kit that's completely interchangeable with the Assault / Plasma / Las Cannon in the Venerable Dreadnought. I'd expect to see a lot of those on eBay.
Pfaugh, they should have removed the heavy flamer option when the 6th Edition codex rolled around, or, better yet, never have come up with it in the first place. It turns the Immolator into just a Razorback with different iconography, which is sad.
What, you mean [url=http://www.games-workshop.com/en-GB/Chaos-Space-Marines-Cultists]these Cultists[/url]?
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Anyway. Orks need a megaboss who ain't Ghaz. Dark Eldar need some more Grotesques, especially since the Finecast one has what looks suspiciously like a flesh gauntlet on its non-swappable arm and is therefore a squad leader without a squad. They also need Vect, Malys, Sliscus and the Voidraven Bomber (though I would expect those last three to just quietly vanish in the next codex).