Jesus Christ this was crazy. I'm looking at a ton of different opinions here and the problem is that MOST of them might actually be correct, while seeming to contradict each other. Things to keep in mind:
Amazon US has Prime, which means free 2-day shipping for any orders that are warehoused and processed by Amazon for a vendor. Free 2-day shipping usually beats anything that cubing stores can do, and in some cases you can get free 1-day shipping like I got with my GANs.
Prime itself does in fact cost money, because it's a recurring subscription. Whether or not you account for the cost of Prime when calculating your overall savings when buying something is an argument you guys can get into, but IDGAF. For the record I'm a Prime subscriber.
I don't know if Prime shipping exists in other Amazon-serviced countries, and if it doesn't, then the free 2-day shipping edge goes out the window. At which point the best shipping argument most likely goes in favor of the major cubing stores, while the best pricing argument goes in favor of the major Chinese cubing stores (and don't forget most of the Chinese stores have free shipping if you meet a threshold too).
The price at Store 1 for Cube A will be cheaper at Store 2, but then if Store 2 has a cheaper price for Cube B, it's really difficult to base any "Store 1 is cheaper because I bought Cube A and it was cheaper" arguments. Not if you want Cube B as well. At this point it's apples and oranges, unless we all place orders for the exact same combination of cubes.
What I'm saying is that there's no one true concrete for sure absolute IWouldBetMyLifeOnIt best way to save money and get a cube quickly if you don't have Prime, but even if you do have Prime, some of the cheapest deals are still to be had in China if you don't mind a longer wait.
Personally, I've had to order several of my limited GAN cubes through the official GAN store on Amazon, because the cubes sold out within weeks on The Cubicle, SpeedCubeShop, and Daily Puzzles, etc.
I ordered my GAN K'un purple cubes on the GAN store, and I ordered my Blossom series cubes on the store as well. The Blossom series sold out at both The Cubicle and SpeedCubeShop within less than a week. The Blossom series is still available, at the time of this writing, at the GAN store, and this has been over 3 months since they were made available. https://smile.amazon.com/dp/B096NSK5MP/ref=cm_sw_em_r_mt_dp_GHJPPT6Q8JXDJX4FRBEE?_encoding=UTF8&psc=1
Again, these were gone within a week if not days at all of the major cubing stores. I had no choice but to get these on Amazon, and I would have opted for the Cubicle or SpeedCubeShop if I could in order to support them.
Not everything is available at every store, no matter how hard you try, and even if some of what you want at one store is the cheapest, the rest of what you want might only be at another store.
Stop arguing over where you got your cube for the cheapest, because it's not where everyone else got their cube for the cheapest. Be mindful of the prices at ALL of the shops, try to put your money at the businesses you like the best. You can hate on Amazon, but if a kid who wants a cube is getting offered a cube, a parent who has no clue is going to trust Amazon's return policy over creating an account with some company they've never heard of before, and we're here to make sure as many kids get into cubing as possible. Mom and Dad don't know The Cubicle, they trust Amazon, and let's focus on getting Timmy his new cube. The rest of us can get cubes wherever the fuck we want and feel superior. God knows most of us certainly aren't getting laid, so why not try to increase our numbers by making sure little kids get into cubing?