Losmandy camera dollies are a better choice for 3 reasons:
1) Flexibility. The 3-Leg Tripod Dolly can be upgraded to become a fully rideable 4-Leg Dolly, or the 4-Leg Dolly can be set up as a 3-Leg Tripod Dolly if one needs to work alone.
2) Floating Wheels on one of the track rails. There is no need to measure a precise separation between the track, you simply approximate a 2 foot (60cm) separation and the floating wheels move in and out to compensate for any deviation in the spacing. This makes setting up a run on FlexTrak almost instantaneous.
3) 360° pivoting seat. This feature truly sets our dolly apart from most other dollies because it allows the camera operator’s body to move effortlessly in sync with the panning motion of his fluid head. Other dollies with stationary seats are impractical if there is any panning involved in the shot.