Well, I haven't tried swiftkey, but I like h-k because you can open it on demand, and it has all the keys so you can do stuff like ctrl-c-p. It also seems way faster to open than the stock kb. I dunno if it would be so good on anything smaller than a tablet though.
I still think the Sony Ericsson Xperia X1 is the best designed phone I have owned. Even though it didn't have the number row you wanted too. And it ran windows mobile.
Yeah, there were a couple of other four-row ones that were ok in other aspects. There were times I considered buying inferior products just to contribute towards demand; doubt it would have made an impact but still kinda wish I'd done so.
Although you'll have to wait til 2018 if it does actually get released. Seems a bit crazy though, 3 CPUs, 18GB of RAM, 768GB storage, and a hydrogen fuel cell-equipped battery.
My favourite is Smart Keyboard Pro. I tried a lot out when I got my last Android phone, and despite the high feedback, I never liked SwiftKey due to the developer's insistence with certain features that "We're right and you're wrong". Hence no way to turn off that annoying click and swipe for certain punctuation marks, and there was another dumb default option that annoyed me too that couldn't be changed (can't remember what it was now).