Considering buying Bitbox02, what should I know about it and self-custody in general ?

Hey guys, After DCAing for few months, I finally have enough on the exchange to consider self custody without stacking to much UTXO. I scrolled the sub and found out that Bitbox02 was a good cold wallet and that it may fulfill what I need (except the price but well, gonna have to invest for a good product for good security). I started reading some stuff on the website before buying one, but gotta ask for those who own one : What should I know about this cold wallet and self-custody in general ? Tips ? Things to avoid ? Since I'm still new to this, everything is welcomed (even the "store your passphrase at a secure place" ????)

Thanks everyone