Yes they are but
4.2.2 ROBOT PARTS AND MATERIALS RULES
<R01> Only TETRIX, LEGO, and/or MATRIX preformed robotics components (i.e. gears, wheels, extruded
parts) may be used.
This eliminates a lot of companies wheels (such as VEX)
But : <R02> In addition to the TETRIX, LEGO, and/or MATRIX components, teams may use additional materials
to construct their robots providing they meet the following constraints:
c. LEGO plastic building parts are allowed.
So:
http://www.brickshelf.com/gallery/zb...reenshot20.png