Finally got the body in, so I put him together and took some pics. I'm using the COOMODEL Standard Muscle Arm Body BD007. First one of it's kind that I've bought, since I usually use the basic $20 body you can find anywhere. But with this being a jumpsuit, I wanted the body to be a little bulkier, and I think it works great. The outfit itself is surprisingly high quality as well. I had to stretch that sucker to get it over the body (I definitely wouldn't recommend a Bane or Schwarzenegger body), but it held, and looks awesome.
The Pipboy is quite nicely done, and looks well worn. The screen is not completely readable since it's so small, but it looks good. My pic is a little blurry, but it's like, 99% accurate to what it looks like: just bearly unreadable. Lastly, the leather is thin and somewhat fragile feeling, so once it's on, I wouldn't play with it too much, but I didn't have any problems with it. The two thin side straps are held in place by magnets in the front, and I thought that was cool. They're not terribly strong, but they'll hold in place once posed up.
Hard to nail down the material, it's like a stretchy nylon-cotton blend, so it has some thickness to it. My only gripe is that the arms and especially the legs are too long, so the material bunches up. Arms aren't too bad, as you can see in the pics, but the legs have quite a bit of extra material.
I would definitely recommend this body to go with it. It's got definition, it's neckless, if you have the head from the armors, and it costs less than $30 off ebay.