A video of the LRW-990 Walker is posted on a Lego Internet Forum, showcasing a few of its abilities. It shows the LRW-990 walk across a field, then breaking into a pseudo-run at well over 60 KM/h, and then slamming all of its feet down into the ground bringing it into a surprisingly steady halt. It then turns around and and begins running towards an example, unmanned ARM-29, and proceeds to kick in the "roosterpit" of the ARM-29, which would instantly kill anybody who happened to be inside. The LRW walks away from the ARM, then charges, knocking it over. The LRW then releases the safety from its integrated weaponry in the form of a high caliber machinegun, opening fire on the ARM-29, puncturing the APC's armor easily. The footage is removed quickly from the forum.
For reference the LRW-990 is not a giant monster like the picture I posted would have you believe. It's like the size of an average car.