The most immediate question is whether the Leg Stand you’re thinking of buying is suitable for the tool you want to mount on it. For instance, some Leg Stands are built for Mitre Saws and others for Chop Saws. Some are even designed for specific tools, which needs to be considered.
In addition to the Leg Stand, you might want to think about accessories, such as Work Support Stops, in which case you should ensure that any accessories you might need are compatible with the Leg Stand.
When deciding whether a particular Leg Stand is right for you, check that the dimensions will fit your workpieces and allow you to work comfortably. You should also think about the weight of the product, which might impact on how you transport the stand and the tool from job to job.