I think both solutions are probably reasonable secure. Personally I use the proton solution, because I like that my data is in Europe and I prefer to pay for services. I like the more transparent and honest business where I pay and get something in return.
I have given up on this series. I’m not even sure I would read the next book if it was released tomorrow. Maybe if the series is ever fully released I might reread it from the beginning to end. It’s like if Netflix published books.