honestly i only trust bitcoin among other coins because i see that bitcoin is 100% legit and its not a ponzi or a bubble.  its been over 8 years since it was intruduced to the public and it is still going stronger today so i guess that it can still go a long run and its worth it if your on to investing for a long term, and if i would choose a wallet for cold storage , i would choose trezor because i see that it was a good hardware wallet based on the users review compared to other wallets.