I'm with Rashaan and Michael. Best Buy, hands down.
That 20% off new games stacks with sale prices. AND it applies to amiibo as well.
If Amazon offers some insane sale price, show Best Buy, and they price match it.
On top of all that, you build up rewards points with every purchase. The more you spend, the faster they accrue. If you use their credit card, even more so. Your rewards benefit can go up to 6% of what you spend. Like Michael says, certain preorders net you additional rewards certificates.
Lol. I sound like I work for them. How do I know so many details? I pick it apart to get the best deals when I'm broke, but still want Switch games.