For the T55 fan who has everything & wants even more here is a custom project for an owner of the Hooben kit who wanted something more substantial than their stock plastic chassis. Photos show current progress but was told this will be offered with full suspension including sprockets, wheels & track, And yes, that lower hull is milled from a block of aluminum.
Xu will offer it as a commission build on his Taobao store once work its complete. No idea as to cost but as that old saying goes, if you have to ask the price, you probably couldn't afford it. Will post more details & photos once finished.