I've had almost all of the different Gameboys before, 3DS XL, PSP and Wii U but my favorite, by far is the 3DS XL. That thing is so comfortable in your hand. With the 2DS, the consoles were a bit weirdly placed so your fingers could get tired quite fast but they've improved this on the 3DS. It is perfectly spaced out - the analog stick and the D-pad. It has absolutely incredible games like the Zelda remakes, Pokemon Sun/Moon, Pokemon Sapphire, Animal Crossing New Leaf, Fire Emblem franchise, Mario franchise and Mario Kart... I think that it has the best choice of games from all of the current consoles. None can come close to it and that's why it is still my favorite.
We shall see how many new games they add to the Nintendo Switch. I don't have it but I really liked some of the games that they've shown us at this year's E3.