I use two non-Retina screens with my MBP in clamshell mode. I've found that the Touch Bar MBP has issues with "Unlock with Apple Watch" when the laptop is open. I think it's trying to figure out whether to depend on the watch or the fingerprint reader to unlock and it always defaults to fingerprint.
I don't feel like dealing with that OR dealing with two screens of the same image quality and one screen with really high resolution. I'm probably going to upgrade to an ultra-wide at some point.