Two things happened at work today....lots of meetings and then free wings and such for lunch. This post almost didn't happen. Nevertheless, we perservere through hardship.
The Swarmlord - An aboslute monster, who suffers a bit from the problem that all Tyrants have, in that he's slow. But he does cut through invulnerable saves, cause instant death, is a super psyker, and can make the rest of your army stronger. Still, at his cost and speed, I'll give him a B.
The Parasite of Mortrex - If nothing more, this is a pretty darn fun model to use. Put him in with some Gargoyles, and he's safer. I'm not really sure about his real utility, but the special ability is going to make your opponent sweat just a little about outflanking. B, for giggles.
Deathleaper - This is one of those units that you can't really look at in terms of killing ability. Instead, focus on how many little things it's going to do to your opponent to make his game harder to play. He can slow down opponents and make their leadership lower. Hard to kill. It's nasty business, and I like him a lot. B+
The Doom of Malan'tai - Pure craziness in a single model. Sure, he could die to a missile launcher. But if you don't kill him, he's going to get all his wounds back, and then some on the next turn, and he costs less than a C note worth of points. A no brainer, and an A+ (and that's assuming that he doesn't hit things in transports, which is debatable until the FAQ).
Ymgarl Genestealers - The crazy folks can be tough and mean, and the ability to come out of nowhere is nice, but you're getting pretty pricey for 'Stealers at 23 points a model. I'd pass on these. B-.
Old One Eye - Yep, he's a killing machine. He's also amazingly expensive, even compared to the amazingly expensive new Carnifex. C-.
Thanks for bearing with me as I worked through the Codex! I realize that as a primarily Fantasy player getting back into 40K, my insights are not revolutionary, but I hope that in working my head around the Codex, I've been somewhat helpful to you as well!