The two best books about powered armor are Starship Troopers and The Forever War. Armor makes a solid third in the trinity. Of course, it's not a perfect book, and I'm not sure that the unusual structure helps it.

The first bit is conventional enough. Felix is a scout, The Scout, a lethal instrument alienated from his fellow man, part of a beachhead on the planet Banshee, a frozen and wind-scoured wasteland inhabited by 8 feet tall "Ants". The mission is simple reconnaissance in force, but there are so many Ants. A fragmented consciousness, the Engine, lets Felix kill and survive. He's one of the sole survivors of the mission. And then he's back at it. Another drop, more Ants, more killing.

The unusual structure is that after meeting Felix, we switch the first-person perspective of Jack Crow, interstellar rogue and brawler. Crow gets embroiled in a pirate's plan to conquer an isolated scientific outpost. He takes along a strange relic, a suit of black power armor, and enraptures the outpost's staff with his notoriety. He and the outpost director, Holly Ware, read the combat-recorded memories off of the armor, experiencing Felix's war. And at the end, it all comes to a head.

This book has chaotic descriptions of battle, of powerful armor against hordes of alien bugs. It's killing without tactics or purpose, World War I like in its nihilism and the detachment of senior officers from the cannon-fodder. Felix's story is great. And Crow's story is just... there. Steakley must think Crow is a much more interesting character than he is, and there's a lot of telling about "the great Jack Crow" for relatively little showing. Still a good book, and one of my favorites, but definitely one with some warts.