[@Klomster] That's the thing, though. In fluff, the abilities of a single marine vary dramatically. In books, they can be as potent as a single marine taking on entire legions of enemies, to standard foot-note level extras. Yes, any Named marine will usually accomplish amazing feats of skill, but that comes with plot armor. In other games, though, their powers vary even more. Some games depict them as being monsters of combat, being more akin to titans than humans. Others make them out to be just tougher humans.

Which is why the majority of people I know use the table-top game as a basis for determining average abilities. For one, the codexes are simply stated as being the most cannon source of information, until a new codex comes out. For another, they compare averages, not individuals.

[@Wraithblade6] The afore-mentioned demolisher cannon shell from his face. That wasn't a joke, that's something psykers are fully capable of doing. It also originates from a point of his choosing, so unless one of the two marines has a null-rod lodged in his cologne, they'd both take a direct hit capable of destroying a land raider. And, I'm assuming, you don't think a space marine is more resilient than one of the imperium's most heavily armored personel carriers. That would just be silly.