The plastic is paper micarta . . which I guess is a kind of plastic, but then if micarta is plastic then so is carbon fiber.
I have a hawk in black MOP and I've handled and given as a gift an osprey in black MOP. I also have an osprey in honey jigged bone. Come to think of it, I also have an older falcon in antique paper micarta.
I'd recommend that you get either an osprey or a hawk in honey jigged bone. The osprey is a really cool little knife . . but it's tiny. You'll use it for opening envelopes and boxes and cutting fine little things . . but you're not going to use it to break down a dozen moving boxes or anything big. You're not going to cut up an apple with it.
The hawk is still a nice gentleman's knife, but is big enough for bigger projects. The hawk is a very slim, knife too. Both the hawk and osprey come with leather pocket sheaths, so they can sit at the bottom of your pocket with keys and change and not get dinged up. After a few months of carry, the sheath will be nice and worn - like a good baseball glove.
It's up to you - the osprey is tiny; the hawk is mid-sized. I carry both depending on my mood.
Regarding scale material: The black MOP I have is pretty, but I'm afraid that if I drop my knife on a hard surface that it could crack. The jigged bone is really beautiful and sturdy. The antique micarta on my falcon is really, really nice, too . . but I wonder if it would be as nice on a smaller knife.
Either way, I don't think you'll be disappointed.
BTW: According to the Al Mar website, it looks likey they're re-issuing the original Eagle this June! That's pretty exciting.