Whether you buy a hairdressing chair with or without castors depends entirely on your preferred handling and use of the chair. For example, if you have service stations in different places in the salon, castors might be important to make it easier to move the chairs from A to B without the client having to stand up. The hairdresser's chairs with castors are usually equipped with a stopper so that you still have the necessary grip when it comes down to it. It is also practical for customers in wheelchairs to be able to simply push the hairdresser's chair to one side quickly. If you want more stability, a chair with a support leg is more suitable for you.
The frame or base also changes the style of the chairs, so you can also make the choice based on the design of the rest of your salon.