the only rules difference from TAR: USA and TAR: Asia is, first episode is a NEL, the teams get to get their backpacks, but no money given on the next leg, and have their money confiscated. and the gameplay is way too simple.
If TAR: USA ratings kept falling, i will say to blame on the TAR: Asia, or maybe Allan Wu, his hosting sucks. i have to say if the ratings in the US version dropped intensively, i am the first to apologise to this.