Even the ABS used on the Echo 1 P90 is pretty rugged stuff. I don't feel like I have to baby mine in any way, shape or form. I'm sure CA's ABS would be just as good or better. I wouldn't be concerned about it. Although I have to say that reinforced nylon is one of the big selling points with me an CA. Without that, it knocks it down a big notch.
Personally though, I'm still quite fond of my E1 P90 and would recommend it to anyone looking for a nice gun with a full metal upper at a really decent price. As for internals, it has 7mm steel bushings, reinforced gears, metal spring guide, and aluminum piston stock, and comes with 2 mags and a 9.6V battery in the box. Ad it shoots 350 stock (started at 365-370 and then settled after a couple of hundred rounds). To me, that's a winner right there considering the price.