I've played one a few times at a mate's house, but didn't really like it. Certainly didn't feel any desire to get one, or that I was missing out by not having it. The controller is pretty poor IMO; uncomfortable and unwieldy, and the whole idea of the gamepad just seemed unnecessary. The name is genuinely terrible. Splatoon seemed okay, but I wouldn't have bought it, and Mario Kart is...well, Mario Kart. I was bored of it long before MK8, and so that didn't appeal either. The other games I've played were, again, okay, but nothing really stood as a must-have.
Switch is interesting, but if there are lots of ports of Wii U games, that's not a good thing, at least for me and my tastes.