Just a short update - the Tamiya cantilevers (part 53490) were finally in stock at the LHS so I picked up a set for the TXT. These are beautifully anodized blue with the word Tamiya on 1-side. As always, Tamiya-quality is high in standard.
The cantilevers are anodized blue with Tamiya's standard high quality, and they are designed with nice curves for a sleeker look. The centre is also relieved for weight. I forgot to weigh these before installation but I think they'd be only a tad heavier than stock.
At the end of the day though, I must say that the stock cantilevers worked great for me and I don't think they would have failed. These aluminium ones are beautiful add-ons though - but the change is more cosmetic than performance oriented. The price tags on these are not cheap either... at 3,300 yen, they'd take a good chunk of change out of your wallet.