Could never get it to work -- connection to the PC (tried 2 different computers, both with Windows 10 installed) was unpredictable, and firmware installation failed every time. Finally gave up after 2 days of trying, because I'm not trusting my cryptocurrency to a device that is less than utterly reliable. Went with a Ledger Nano S instead.
UPDATE 7/27: Finally got it working by connecting to a USB 3.1 port directly on my motherboard (the computer's back panel) -- worked instantly and perfectly. The software is very polished, and the device is more straightforward to use than the Ledger (no apps!). I'll post another update after I've used it for some length of time.
UPDATE 8/1: I've now given the Trezor a thorough workout, and I have to say that I really love it. It's very easy to use, and it connects reliably every time (do NOT use a USB hub, as mentioned above -- the front panel of your computer may be using an internal hub, so if you have a desktop, use one of the USB ports on the rear: those are on the motherboard itself). Entering your pin is quick and easy on the touch screen, though big-fingered me sometimes hits the wrong number, because the screen is small. A nice security feature is that the device changes the positions of the numbers each time so that no one can guess your PIN by looking at the fingerprints on the screen, and so it's harder for people looking over your shoulder to guess what you're entering.
The wallet software is best run under Chrome, which supports WebUSB. It's very simple to use, and there's a clever integration with Dropbox to allow you to label your transactions and addresses if you desire. (You want this, I promise.) My only complaint about the wallet software is that it doesn't support Ethereum/Ether directly. The Trezor itself, does, but you have to use a different wallet software (MyEtherWallet) which is not nearly as simple as the Trezor folks make it sound. They are rumored to be working on adding Ether support to the Trezor Wallet software, but until then, I'm using my Ledger Nano S for Ethereum transactions.
When using a hardware wallet like the Trezor, you need to know you can recover access to your funds if something happens to the wallet (loss, theft, destruction, etc.). Before sending any money to my Trezor, I wiped it, then recreated it using the recovery seed that's generated when you first initialize the device. It worked perfectly. I bought a Billfodl to secure my recovery seed, and I'd highly recommend that or something similar to keep your own recovery seed safe. After all, if something happens to your wallet, you can recreate it using the recovery seed; but if you lose your recovery seed or someone steals it, your funds are gone.
tl;dr -- 5 star device, minus 1 star for no Ethereum support in the Trezor Wallet software