/forgot to add, that the I like the labeling feature as well.
If you carry your Trezor with you to use with Mycelium on Android you will appreciate the light weight. Also Trezor works perfectly with Mycelium, no problems at all. I tell friends who get a Trezor to consider it disposable and buy a back up in case you lose or break it and have to restore from seed.
I got a KeepKey to compare with Trezor and it is very pretty, easy to set up, but does not have the passphrase protection that Trezor has, at least on the Chrome extension. KeepKey is supposed to work with GreenBits on Android but after trying all evening I gave up and wrote support.
KeepKey has its own quirks as well. Currently it does not work with a wallet on Android and you can not use passphrase protection for your seed with the Chrome App. Well, using a passphrase is important to me. Should someone manage to get my Trezor seed it is worthless without the passphrase. I think the KeepKey designers are trying to keep it as user friendly as possible for new users.
It is possible to passphrase protect accounts using KeepKey but you have to use Electrum instead, and it is a bit of a chore installing the Python dependencies you need on Windows. You can check out the instructions here.
In contrast to KeepKey multiple passphrase protected accounts are a snap to set up on myTrezor.com and you can use those same accounts on Mycelium on Android. The user manual for Trezor is much better than the documentation provided by KeepKey. I think they just need some time to add better user documentation to the KeepKey site.
I am still working with KeepKey to enable phone integration, there apparently is a problem with GreenAddress they are working on and I will update my hardware wallet review as I am able.