Eve Paul,
Yes they do seem more aggressive than the original MT, the pattern is however alot more closed which should hopefully mean less road noise. They also have better side lugs which extend further down the casing much like their competition Krawlers. Sidewall puncture resistance has also been improved.
The yanks seem to like them, but they do far less mud plugging than us. I think they will be better for overland travel than the originals (quieter/not so aggressive) whilst providing far more usability than AT's.
G