I want to share my experience with Hongyi too ! I hope that can help you if you really want to deal with them.
I started dealing with them four years ago, through a certain "Lucy" (with whom I always communicate by email ever since). It was not far from their very beginning with sex toys and "cup holder" (they learned what a SPH is the hard way

. They did not offer much choice at that time (two or three My Little Pony dolls).
The first doll I bought from them was a version of their first Twilight Sparkle, a little modified.
At first, the quality was clearly lower than what they do now:
- The painting was one of their biggest failures (it faded at the slightest contact with water). Some people have been more fortunate than others about it.
The last doll I bought has no such problem, but I could not guarantee that would be the case for each of their products. This is a hit or miss and that's a shame.
- The seams stood out much more than now (they let well-recognized white lines along the toy. For some, it was at the expense of the aesthetics of the toy. Personally, I didn't care).
I bought several dolls during this period (at least five), and this is what I could observe;
- Prices have fallen a bit since then. I paid some toys over 500 euros at the very beginning (and creating a design is really very expensive). Now, with their promotions in June and November, one can buy one of their doll in stock for about 200 and 300 euros, maybe less with luck, without paying postage (which are rather high, but I never had any delivery problems. I live in France and all my parcels took less than two weeks to arrive once the toy was manufactured).
- The quality has improved over time. They manage to make more complex shapes, more cleanly (the seams on my first toys were pretty awful).
- If you order from them, you should not be afraid to communicate your desires (they have made great progress in terms of communication... at first they didn't spoke English as well as they do now).
Don't hesitate to specify the number of valves and air chambers you want. It is also possible to specify the thickness of the vinyl (most of my dolls are made in 0.4. I have one or two in 0.25 and I like them maybe even more, they are more pleasant to cuddle) and the size of the toy. You can also ask for other colors if you want to customize an existing design more, but it will cost more. Finally, you can add an SPH to any location, on any toy

for designs that didn't originally have them, this is also an extra cost.
- The quality is very good in terms of the strength of the seams. I weigh quite a lot and I tend to slightly overinflate my dolls ; I've never had a serious break. I've had a few tiny leaks, but I'm pretty wild with my toys and some shapes on some design don't make things ideal (a few drops of HH-66 and the dolls are ready for next round that said).
That's pretty much what i can say about Hongyi. They are not perfect, but they are good enough (and now, they provide designs that are really worth it).
Hongyi is expected to hold a promotion around early November (they do that every year since three years now). If you want to try one of their toy, this is the best time (the delivery may be a little longer than usual since a lot of people will enjoy it too, but it's worth it).
Sorry for my french english
In any way, good luck with your first time with Hongyi.