Alot of it is with the construction of the struts and the damping cabalilites. All the Teins have 16 levels of dampening capabilities. But the strut cartridges used are not the same on all models. For example the tein basic and Flex use the same strut cartridge, but my Tein Type HA's use a totallly different higher end strut cartridge. The higher end units tend to have more dense thus more responsive gases. In the case of the FLT-A2's they utilize nitrogen, much like Ohlins does. So the piston speed and dampening force is increased and thus greater confidence, predictability can be felt with high-end units. In addition to that the cartridges on the FLT-A2's are inverted, upside down if you will. This gives you almost unlimited adjustablility. To add to that, the FLT-A2's have adjustable mounting brackets. So you can adjust the height of the spring perch and also can adjust the height of the lower mounting bracket. The later being a very huge benifit. This can permit the spring and dampening force to be at the optimum and then adjust the height of the lower bracket. Which is Excellent for corner balancing. were as with the flex you can only adjust the height of the spring perch. Which require you to find a happy medium when corner balancing these. You have to sacrifice a little rebound, spring rate, ride height to achieve the same goal. Now if you go with a Higher Tein unit, like mine the Type HA, the strut cartridges used have great dampening capability and quicker shock rebound. They do not have adjustable lower mounts, but make up for it with helper springs to allow you to get it all where you need it and have the helper springs keep it all in place.
So basically, you need the top of the line Tein Units to compete with the top of the line JIC's
