I certainly wouldn't call them perfect and none of them could even touch my personal top-10-ork-list with a 10-foot pole.
But still, I like 'em. I wish I had more different poses and less of the '87 Ork Raider variants but eh, better to have those ork boyz than no ork boyz at all.
As for the plastic arm guys, they are taller, have crisper detail and are just chock-full of whimsy and uniqueness. They include some timeless designs that still define the look and feel of Orks today.
The downside is that they are missing their arms and weapons and one has to find suitable ones and put them on.
This is where I draw the line when it comes to era-appropriate. If I have an arm or a weapon that fits, on it goes, no matter whether it really was available before 2nd Edition.
So far, I've assembled 17 plastic arm guys (4 more to go) and I can't even begin to imagine the amount of time and effort it would have taken me to assemble five dozen more, let alone where I would have taken 120 extra ork arms and guns and choppas. Impossible, or at least to me it seems that way.