Being clean and polished ("perfect" as you put it) isn't really what would fit in a codex. Even the digital illustrations in recent codices are grittier. Well, I guess this style would work with eldars, though. This one, however, [link] looks about right.
Sure, but that's a warpriest, as his red robes indicate, and his equipment doesn't look new. But I'm more talking about the visual aspect of the picture itself: very few texture effects, an even, plain lighting, a neutral pose, very readable, painted carefully rather than expressively. It almost looks like a 3D rendering with basic coloring. Very adapted to a character portrait in a RPG book, to let the players have a clear view of the characters they're playing and encountering, but not at all adapted to a codex, in which the pictures are there mostly for ambience.