Welcome to the forums!
Like you, I came from an iPhone although I have to confess this isn't my first Android phone and i'm keeping the iPhone 5 to use as a work phone. Check out my thoughts in the various threads on the HTC One forum. Mine are completely subjective, I realise, but I am an iPhone user through and through so hopefully my thoughts will be useful to you.
You've made a good choice, I just cannot stop using my new HTC One.