They got a general point preordering is pretty bad in many cases as the prices in months drop and hard. But if you end up buying for a certain system, publisher, or developer/publisher which is hardcore into not discounting, it's a good idea.
Nintendo rarely lowers prices unless they over produced a bomb (like Elite Beat Agents went from $30 to $10 in months) or never unless a Selects title hits 3-4 years later.
I've used Prime to get 20% off on Switch games otherwise I've not bothered. Every game but one I got on the system came through there for the discount.
That first post has Sina More EX listed for PS4, it's also Switch confirmed too for $30 and with that cut it's down to $24. Totally worth it. They bother to date it I think I may just do it, and I'm flip flopping on doing it with Cave Story. I'm pretty tempted to just sell the unused 3DS one I have off since it's an original w/that 3D sleeve to cover it and then some a little.
