One of my AR's is a plinker. I bought it because it was cheap and my other AR's are my babies and I can't bear to abuse them. I also wanted to see if a cast receiver was any good. I only use it for range stuff, so it has held up pretty well. I actually like it alot.
The finish is kind of rough, but not really that big a deal because I actually use it and it is not meant to be a safe queen. For some reason, the handguards do not have the heat shields in them, though. That is the only thing I found to be incomplete with the rifle. It comes with the A2 pistol grip (not that wierd old style olympic pistol grip that you might see on some pictures of the plinker) and the A2 buttstock. It's pretty standard except for it being cast and not having the liners in the handguards.
If you want to take it out into the field for hunting, you might want to consider a forged receiver. For about a hundred dollars more, you can have an Olympic CAR-97. Other forged AR's (Bushmaster, Rock River, and DPMS) also cost about the smae as a CAR-97. The savings isn't that much more and you get a slightly stronger rifle.
I know one guy on the boards had a plinker break on him just forward of the mag well. This was bound to happen at least once with a casting process as air bubbles can occur when the molding process occurs. I wouldn't worry about it if you do get it, the chances of it happening are slim. There are guys with cast receivers from way back that have never had a problem However, if this is going to be your first AR, get a forged receiver. The first AR will always be a cherished item, so make her as nice as possible.
I say first because it surely will not be the last. Seriosuly though, the plinker is decent. It will serve you well for your intended purpose. Olympics are prety good generally. The fit and finish will not be as nice as a Rock River, Bushmaster, Armalite, or even DPMS. However, it will function perfectly and will last more than a lifetime.