Are Trezor wallets safe? Short answer: YES!
The Trezor PIN based security system is the first layer of protection for your Bitcoin. If your Trezor is ever stolen having a strong PIN is imperative.
Your Trezor is protected with a PIN that you personally set. It can be up to 9 digits long using the numbers 1 thru 9. If you decide on a 4 digit PIN this leaves 6,561 possible combinations. A 9 digit PIN would be 387 million combinations. If someone attempted to brute force your PIN they would be met with stiff resistance. Each time the incorrect PIN is entered the wait time increases by a power of 2. Trying 20 different PIN numbers would take 150hrs! 30 PIN entrys' would take 17 years. 100 PIN numbers would take (along time).
Each time a PIN number is entered incorrectly the Trezor stores that in its memory. Power cycling the Trezor is pointless. As you can see having a strong PIN is essential. For added protection and additional layer of security; consider using a passphrase in addition to the pin number. Keep your Bitcoin safe PIN protect your Trezor Hardware Wallet!
Pro Tip: 11% of passwords used are 1234. DO NOT use the PIN 1234. Also try to avoid repeating or sequential numbers . Example 1111, 2222, 1234, 5678.
We a currently working on a video tutorial showing how the Trezor PIN method works, stay tuned!