Since my M8 is effectively an expensive brick right now, I'm going to avoid HTC until they come up with an entirely revamped hardware spec. Yes, it worked beautifully for months ... until the dreaded permanent "disabling airplane mode" appeared - SIM is no longer being detected. Swapped SIMs, reset to factory, flashed alternate ROMs. Still stuffed.
If you look through the forums, it's a common problem without a reliable solution.
Also, I have to agree that the speakers make the phone way bigger to handle than it needs to be, and yet somehow I often missed hearing the phone ringing while it was in my bag. Sure, they sound "good for a phone", but really, still shite. If you listen to music through headphones predominately and don't much use speakerphone (what is it with the morons these days walking around with it permanently on speakerphone and bellowing into it like a walkie-talkie?), then that feature isn't really much chop.
Otherwise, yes, a nice phone without too much cruft in the OS other than the stupid "blinkfeed". Has that gone in the M9?