Where to buy Digital Switch Games (Nintendo vs BB vs...)

Hi RFDr's,

I'm a bit new to the switch, as I am getting it for my kids for xmas. I wanted to buy Mario Party and Overcooked 2 today, but which online retailer is going to be the best value to buying digital downloads from?

From what I can tell, nintendo i get 5% back in usable credit for future games, so right now I think thats the best bet for me, but im just curious if you guys have any other opinions.

Thanks and greatly appreciated.