Undoubtedly both these products are good and I'd recommend either of them to anyone that needs to take their crypto on the road and may need to make a transaction from any machine, including ones they are uncertain about its integrity.
Ledger Nano S is a recent purchase bought on the grounds it was first to support DigiByte, something important to me.
I also believe that both are great, but I purchased the Nano S, and I'm very satisfied with it. It was cheaper and I believe it will also support Monero before the Trezor, I also love how I can use it as a U2F key, which is kinda fun for the websites that support it.