Hi,
I have the Harmony Hub and Nick is right, the hardware is really good, but the fact I have to say 'alexa, tell harmony to turn on the tv' is a pain. If I say 'ask harmony' it does not work.
I have used IFTTT to 'trigger tv', but the more clouds involved, the slower and more unreliable it is.
There is a Broadlink RM Pro Wi-Fi Smart Home Automation device for a fraction of the cost, and it can be setup to work (via IFTTT or Yonomi, can't remember), but again, I'm betting the various devices it has to pass through will cause a delay.
Th Harmony Hub is laborious to set up, so much so that I have only basic functionality after having this for about a three weeks. I'll configure it properly when I have time.
I guess it's like the Hue Lights, after asking a couple of times, if it isn't working for some reason, it's easier to just press a button that argue with Alexa.
Kenny.