Have seen them on Facebook but don’t know anyone who uses it. I use Dinitrol products, excellent. I also use a rust converter on anything bare or inside door, chassis etc. Rust converter was once used at our gas terminal on rusty pipes and structures just to slow the rust, years later these are still the same condition.
These folks have a good process to copy or they charge about £700 for a full service:
https://preserveprotect.co.uk/