Another Nova Prime user here. Occasionally I swap back to the Oxygen launcher, but then come right back to NP. If for no other reason, I miss the unread message count bubbles that I get with NP/Tesla.
Google Now Launcher for me. I occasionally use Nova Prime but find it a bit dated these days. I also really dislike the pop up menu when long pressing an icon - don't know why...
Nova for me, although I love how buttery smooth the stock OOS launcher is, would be good to show to iPhone users to show them there are some much, much, much cheaper alternative phones out there.
I used stock for a while then tried Google Now, Nova and finally Action. Bought Action, sticking with it. I liked Google Now, didn't care for Nova myself.