Dimensions are a little off - 40x32x10cm is closer to featherweights when it comes to size. For something very similar to Sewer Snake wed be talking about 120x90x20cm.

And am I missing something with titanium? 5mm titanium flimsy? I saw a 6mm piece on Tiberious at the FW champs and it was rock solid. I also heard how much of a pain in the asp (:wink it was to cut that 6mm piece so I think 5mm would be fine.
As a chassis material, I imagine it would be adequately strong enough, especially if a sturdy construction technique is used (e.g. interlocking parts, reinforced by welds - seemed to do the job well on an Aussie FW undercutter)