I have not seen these in person, but I have heard they are just like the original. I would suspect these are from the mold which they used to make the "extra" LCVPs for sets like iwo jima, and dday, where the wheels were the same color as the LCVP. I also read something by Rick Eber that even the turreted guns were a tad smaller from this marx mold than the one from the full vehicle mold.
These reissue LCVPs are also stiffer plastic, maybe even brittle from talk I have heard.