Got my white Tangzu Wan'er a few days ago and will post impressions here as there was some discussion of this and other sub-$30 IEMs earlier in the thread.
Delivery was very quick, took just over a week. I've had some things take longer to arrive domestically recently! (we have mail strikes here in the UK).
Note on shipping, however: I bought the Wan'er on sale ($15 from $19) but was not presented with the option of free shipping, only $5 shipping, but when I added the Tripowen Zombur cable for $9.99 I could select free shipping. So I ordered the Zombur with the Wan'er just in case the stock cable had any problems, or if I wanted a mic. Looking now, if you add the Wan'er, currently not on sale, to your basket, for $19, you are presented with free shipping. So... the Wan'er is actually more expensive when not on sale? I might have done something wrong, but it's something to be aware of (we are talking meal deal amounts of difference of course).
My IEM reference is Etymotic ER2XR, and headphones HD6XX. My intention buying the Wan'er was a) see what $15 gets, and b) hopefully find a shallow-fit alternative to my ER2XR for when this is unnecessary/uncomfortable e.g. lying in bed.
Cable
Following on from above, I have no major complaints about the stock cable anyway. It looks very nice, The stress reliefs are well designed, and I love the low profile right angle connector which sits flush against my phone when plugged in. It feels soft and not microphonic in everyday use: running a fingernail along it is audible, but walking around with it bouncing against your clothing doesn't transmit any noise.
Cons: tangles easily, no clip, no adjustment ring, L and R cables leading up to the IEMs are quite thin (may contribute to the tangling). Pretty minor though.
I'm yet to properly try out the Zombur cable I bought, but it definitely doesn't look as pretty as the Wan'er cable, especially when plugged in (black fabric braid + transparent white and gold does not go together). Maybe I will like it, but if you want a mic it seems a better deal to simply get the Wan'er with the mic cable, unless you particularly want a separate cable without a mic.
IEMs!
These look great. I think they look even better in person. The faceplate is behind a few mm thick transparent plastic which gives a pearlescent effect in the right light. I don't like the black version from pictures, especially as you still get the white cable which fits perfectly with the white version, but maybe this looks better in person too.
Built entirely from transparent plastic with a metal nozzle (I think, that's what it looks like). I don't think it would withstand being stepped on but otherwise appears it would hold up well. At least it is made in such a way that there are very few things that could go wrong e.g. I've seen pictures of the Truthear Zero faceplate coming off--that's not going to happen here. Reviews have described this as looking/feeling cheap, I disagree.
I have always struggled with shallow fit IEMs and this one is no different. I tried all the included tips, the large wide bore ones were the best but even then I found Final's E tips better because the silicon is thicker so I found it easier to get a seal without deforming it.
Isolation is not as good as Etys but better than my HD6XX. Walking around listening to dense music like metal could mask low traffic sounds without turning up the volume too much.
Sound is exceptional, I perceive it as pretty much just right. I don't believe in the concept of 'technicalities' so don't accept there can be a transducer which excels in tonal accuracy but somehow has deficiencies in 'technicalities', especially as the line usually goes 'but don't expect too much, it's only [insert price below $500 here] so is not the most technical'.
I don't have my own 711 coupler, so going off measurement's by others. There is a lot of variation out there, however, and we don't know who is following best practice. There may be unit variation too. Anyway, most measurements show the Wan'er pretty much matches the ER2XR in the midrange but has up to 2dB increase over most of the bass range. Then treble differs as of course we have deep fit with Etys, though the Wan'er maybe has a different slope in the treble also. Hard to tell with the peaks.
I'm still undecided on the bass. I think the Wan'er is definitely a little too warm objectively speaking, and I've been using a peaking filter at 150Hz of Q=0.8 to adjust this: -2.4dB works well for most songs, up to -3.4 is good but more sounds too thin. Subjectively, the warmth is actually nice on some recordings however. As usual the differences in recordings makes a bigger impact than slight variations in transducer tuning. It's definitely acceptable without EQ.
Additionally, I think Etymotics give you a different sensation of bass due to being shoved so deep in your ear. In short, whilst the Wan'er is at the upper limit of what I think is acceptable bass quantity, if it were a couple dB less that would be fine too.
The mid-range is perfect. EQing in a couple more dB around 3kHz to fully hit that Etymotic target does add a sense of 'bite' or 'clarity', especially to guitars, but I'm not sure it's objectively accurate and it sounds worse on more things than it sounds good.
I think the treble level is perfect too. Like the ER2XR, it's way below Harman, and that's just how I like it

it simply sound correct. There is something slightly unrefined about it, e.g. sounds in that range can sound less distinct, more mashed together, than I'm used to, which I think is down to the resonance peak inherent in the shallow fit design. I'm spoiled by my Ety christmas trees.
Soundstage schmoundstage
You need a proper desktop DAC and amp combo to feed these enough juice though. Gotcha, no of course you don't! Listening on my phone I barely had to turn the volume up at all.
Some people like getting different headphones for different sounds. I like consistency, and now I have 3 headphones for different use cases which provide broadly the same tonal response.
Overall these are great. If you are ordering something else from Linsoul I would just chuck these in your cart for a try. If you are an Ety believer like me, I would highly recommend these if you want a shallow fit or less isolating alternative.