I don't run your series, but I completely disagree with this rule. We can probably argue until the end of time about safety devices and their worth. I think it should be up to the driver to decide which seat he feels is the most comfortable and safe for his personal use.

I know of more than one instance where a doctor has told a competitor that the full containment seat most likely increased or possibly caused an injury in an accident. Remember, sprint cars are not stock cars, and the way they crash are completely different in most instances.