Very very positive so far. I was incredibly hyped for the Switch and it has absolutely lived up to that hype. The Joycons are comfortable, the grip makes them a great controller (I was about to buy a Pro Controller, I won't be doing so now). System itself is great too, very fast, the UI on the menus especially is a joy to navigate. I used the Switch on a flight from one side of Australia to the other and it lasted, playing Zelda,for the entire flight (4 hours).
I honestly haven't found anything negative so far. I picked up Snipperclips and Bomberman as well, but have only played 30 minutes of the former and none of the latter.