Is it worth it to leave a High Paying private job for a relatively lower paying Federal job?

I want to work towards getting a PE license. However, at my current company there are no PE certified engineers.

It is however a very nice job. Good pay, extremely flexible schedule. I have interviwed multiple federal agencies and their offers are about 20k lower but they do have a chance to work under a PE certified Engineer.
What would be a wiser decision?

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