Rina Is this your first experience with chastity or have you been exploring for a while? The belts you suggested are both high-end. I'm sure they would both be good investments if money is no issue.
I know a lot of people dislike cheap belts but some of them are okay, especially if you are just finding your way into chastity. You can pick up a cable belt that is a rip-off of the Fancy Steel one for well under $100 online.
Not saying this is the perfect solution, but it might be a good option for you for the first year or so. It would give you an idea of what's possible and what you would like to improve when it comes to your "forever" belt.