It's legit. When epic 40,000 came out the Eldar didn't have much representation in 40k beyond the falcon so epic 40,000 spearheaded a revision of the eldar vehicles. Most of the old tanks like the warp hunter, doomweaver and tempest disappeared and were replaced with mk1 versions of the (now familiar) fire prism, night spinner and scorpion.Now one of the things they tried to do with epic 40k was detailing the vehicles. It was hard to find an imperial tank that wasn't buried under searchlights, netting and bedrolls.Sll this means that the epic 40k eldar range was a little experimental. A testbed for a new eldar mech look. Their war walkers had wings for one example. Those hexes you see on some of the eldar tanks were an idea for what extra armour plating looked like when the eldar did it. Meant to add some variation to the tanks. I rather liked it, but needless to say, it didn't stick.
Oh yeah - and the reason you don't see it represented on epicollector is because there were multiple versions of the eldar tank hulls. They came in both "factory fresh" and various "hexed up" flavours for variets. Epicollector doesn't seem to have them all catalogued.
Thanks for the info. I have the many of the classic falcons (20 I think) but am just now updating the force.