AliExpress might be a little more cumbersome to get set up with than Amazon [or get used to], but it’s almost as easy afterwards.
You have to be wary of more things: Who is the seller [learn to spot good vs questionable], what exactly are you ordering, and how much, who has free shipping and who doesn’t, and where to check for discounts.
I have ordered keyboard parts from AliExpress since 2018.
They have a lot of sales, and you’ll learn how best to utilize seller + global discounts, over time.
As for Domikey, they do come down in price sometimes, but very strategically. I had my eye on Domikey Hush / Deep Sea for a while. It’s usually $186 CAD. It went down to $156 during a sale, and a global AliExpress discount brought it down to $144. At that price, it was more affordable.
Clearly, they had too many Hush sets. It’s good to keep track of inventory: Domikey went crazy producing sets not long ago, and they charged near-GMK prices. But that wasn’t likely to last forever, and indeed discounts set in.
Worth checking what else they advertised widely. Sunday-Monday there was a sale, including some Domikey sets, but I doubt they went down as much as Hush did. Some discounts stack, which made the all-in-one set [normally high-priced] more of a deal.
The AF SA, MG, and fake SA keycaps, as indicated earlier, often go on sale and generally have low prices to begin with. During the recent sale, Shenpo also went down to $37 CAD for a base kit. That’s way cheaper than Amazon. BTW Amazon was charging list price + shipping for Domikey Hush before, I think. They wanted $80+ CAD for 90 AKKO POM Brown, whereas it was $49 during AliExpress sale.
Which brings up another interesting point. Amazon is often a middle-man between you and the Chinese manufacturers. So you end up paying list price plus shipping, often from the same storefront that exists on AliExpress [but without AliExpress sales]. So you can skip that and order more closely from the source. [Sometimes Amazon is cheaper, like with custom cables].
Some things that often go really cheap during sales: Feker Pandas / Matcha, JWICK T1 and other JWICKs, AKKO switches [$27 CAD shipped for 90 Cream Blue / Yellow!], OUTEMU silents [same price], Gateron Pro and CAP series [similar price], AULA/LEOBOG switches, fancy springs. Things that get weak discounts: KTT and Kailh switches, High-end Gaterons. That that rarely get discounted: Cherry, SP Star, Durock/JWK. Also, the fake Pandas aren’t $2 for 10 anymore, so maybe they aren’t overstocked anymore.