I understand iMessage benefits, in fact, my daughters and wife all have iPhones so when I change to iPhone every once in a while I use it with them but not for messaging but for the new games within the apps, but even when I have an iPhone as my daily driver, I force them to use Whatsapp, I simply created a family group on it and all the communications go through it.
I've never been an SMS guy, in fact I kind of hate it, like I said even when I can use iMessage I never use it as my regular messaging option, so one thing I'm sure, a single feature like this one, no matter how good it can be, won't dicatate which phone I'm buying, I simply can't see myself involved in a situation that I must say; iPhones bores me to death, I hate those huge bezels, the HD IPS screen are not on the same league as the QHD AMOLED screen but I can't leave them because I use iMessage, or FindMyfriends in my case. I always look for an alternative, for family, WhatsApp and even Google Duo and the new Google Location Sharing to know the whereabouts of my daughters. For the rest of friends, if they don't have WhatsApp or Duo and not want to use them, that's their problems, not mine, if they need to contact me then they must call me instead.
Just my .02...