I think the blue is purposefully meant to stand out, you wouldnt want it to be the same colour as anything else in the army.
Ive got a heap of ultramarines, and the only things Ive used greens on are honour laurels, which are dark green, with highlight, and plasma guns, which I have heaps of.
And those are a very bright green.
Marks them out a mile off.
And maybe he used special marine glue?
sometimes i have trouble believing how people can rate these models 8 or 9, i ask myself, is there anything that can be done to make these models better? no. perfection. 10. please take these guys to the demon and win best chapter!