I have a standing version of this gym and have had it now for about 3 years. I am pretty sure mine is made of PVC that has somehow been manipulated to look like wood. I could not tell this from the upper part of the gym but the post that goes into the base pulls out and I can see it is PVC.
I have had all but my macaw on this gym and they all like it. I got a large floor model that came with a smaller hanging gym. I've gotten so many playgyms that I ended up putting this one in storage for the time being -- the base is made of wood and one of my birds got down there and did a good "reconstruction" number on it, or else I would probably still have it out.

Other than for the wood base, the rest of it is pretty much indestructible from what I can see. I use the hanging part all the time. Btw, the bowls in the gym are very secure and I've not yet had a bird get one of them out. That is a bonus in my book! Thumbs up from me!
I got mine off e-bay and remember that it took a while to get to me -- I think around 6 weeks or so.