A nightmare in plastic! Thankfully those spindly central supports have spares in the kit. You'll likely break one or two just getting them off the sprue. There are some tiny collars that fit between the two halves of the brake units. These are by far the smallest components I've ever seen in a kit. I couldn't pick the up without tweezers. I had to fabricate one replacment from scratch after it sprang out of the tweezers and I heard it ricochet somewhere on the other of the room. I didn't even bother trying to find it. Those cylinders sticking out from the sides of the brake shoes are separate parts too, each about 3mm long.
I took a look at these wagons in storage the other day. See those spindly things sticking up from the corners of the guard rails? Guess what's broken off. Go on, have a guess! If ever a component needed to be made from a bit of wire it's these things.
The sides of each wagon are a single piece. There is quite a mismatch between the two halves of the mould which necessitates a lot of cleanup, especially around complex bottom part. You know, where the springs are. That was a few evenings work and a lot of cramped fingers.