I've heard great things about the Trezor, however I've personally bought the Nano Ledger. Haven't used it yet.
Just beware whichever you end up buying, try to purchase directly from source, because there are scammers purchasing these opening them up and reselling them on Amazon (while having stolen the private words to recover the coins)
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Does not matter if they are opened. You cannot steal the private words. The words are set up by you by initializing the device. If you get one with seed words already initialized then you reset the device and reinitialize it with new seed words. Never use any device where the seed has already been done. That is a scam that is easily defeated by common sense.