In maya there is a really handy feature called "playblast" which renders every frame of your animation in the viewport and strings them together in a preview movie. Is there a similar option in Max? If I just play the animation in the viewport it drops frames.
Under the Animation menu at the top, then select "make preview" and you can save out to an avi or quicktime. If you want, you can also check out the RAM player (in the render menu) to play it back so you can scrub frames like in Fcheck.