TL;DR
Having a choice to go independent is a privilege that not many people have. I will share a secret; all great passionate developers and software testers that I personally know took the leap and went independent. The post is based on a remarkable book written by Chad Fowler, The Passionate Programmer.
Going independent is hard. It means that you will work harder and you will lose a big company security nest. No more paid procrastination and collective blame. You and your passionate software tester skills are alone in front of your client. Your project deliveries will always be precise because the client knows what he want’s for his money.
On the other side, all work goes into your pocket. There will not be a fellow software tester that was riding along with your work and success in a big company. Your career investment decisions will be put on the test.
You will have to learn how to market yourself (conference speaker, blog, or article writer) and gain valuable clients that need your services.
You will learn how to set your price to not go bankrupt in your first month.
You do not need to leave your safety nest immediately. Try to do a project for a client in your spare time. Maybe you would fail, perhaps not. But this would be valuable practice for going independent.
What I like is the possibility to lower the paying hours for some time while doing a project in some new framework/programming language. Remember, you are the boss, and you are responsible for the company’s money.