I have never been a fan of the current plastic Guardian models. They definitely are showing their age and unfortunately because they are already in plastic GW will most likely not release a new kit anytime soon. Added to the fact that the two squads of the plastic ones I have were already painted when I got them and the previous owner didn't bother to do the little things like different poses or mold line scraping. I love the detail and individuality that the older metal Guardians posses. You can field a unit of 10 models that all look distinctly different. So far I have two and half squads worth of minis off ebay while still looking for more.
As to the paint scheme it fits my vehicle scheme of Alaitoc. I'm looking to update my 10 Pathfinders next.