Mickeyb, your private keys are on your trezor and never leave it, thus any malware on your PC can't get your private keys. The transaction is created on your PC, then sent to your trezor to be signed. The trezor then requires your pin code to sign the transaction and then the signed transaction is sent back to your PC to be broadcasted. So in that regard, yes your bitcoins are 100% safe.


Now a weakness of having viruses on your computer could be that the address that you want to send the coins to can be modified before your PC displays it. IE you receive a PM and the virus changes all bitcoin addresses in your webrowser to their address or if you copy/paste it changes the addresses in the clipboard. So then when you THINK you're sending the bitcoins to the right person, it could actually be the wrong address. That is the #1 thing I would watch for.

I'm sure the trezor team can give you better descriptions, but that's my 2 cents.



By the way, I finally received my trezor 2 days ago and I LOVE IT. Amazing product guys, keep up the good work. Also future integration with electrum is PERFECT for me