Philip, the shafts appear to be steel, and the G uses taigen electronic so I agree that the difference is mainly the gearboxes. I think I may one day upgrade this to hobby grade electronics, even though it will always be an airsoft tank. Also, I know the tracks on the G are way too loose, but it drives so well I don't think I'll mess with it. If it ain't broke, don't fix it!
I can definitely recommend this hull. So far I can't really find any flaws and I'm VERY glad I bought it. Now I have to decide what to do with the G, but I'm pretty sure it will keep the hull its got and just get metal roadwheels, asiatam if I can afford it, and mato if not.
Kizwan, No, the HL 2.4 wouldn't lock a track, but that's mainly because of the boxes. The HL 2.4 works fine in the mato PIII so that's where it will stay for now.
Now to take everything apart and get some paint on it! Then I have a couple ideas inspired by Norm for the smoke unit and I think when I get it all together it will be pretty cool. I'll keep ya posted.