We have used two Yingxing SMT660s for about a year now (2018 models with the single conveyor). They are rebadged HW-T6SG-64F developed by Beijing Huawei Guochuang (
http://www.smthw.com), although I believe YX buy them in part form and assemble themselves as there are some subtle differences from the other HW-T6SG-64F clones with things like fixings, etc. You can also buy them for export from Wenzhou Zhengbang. Both YX and ZB OEM them under license.
Ours do 0402 with ease. We have no requirement for 0201 so haven't tested them. You used to be able to order them with belt X axis so be sure to specify you want the ball screws if they are still optional. For component detection there are two cameras - a high quality single camera and a smaller but much faster camera for each head that can process each simultaneously for speed (so 6 cameras or 8 on the SMT880). We only use the high quality camera for 32 pin chips and above, the fast cameras work well for everything else (including checking polarity on LEDs, etc).
The software is not developed by YX and is provided by Huawei Guochuang and rebadged depending on which OEM is supplying it. The main software itself is a .NET WinForms application which although obfuscated can be quite easily converted back into source code and modified to suit. We needed to do that to fix a couple of bugs, and adapted the workflow to fit in with our processes. The software code is horribly structured, but is actually quite comprehensive and as all of the machine control, visual processing, etc, are handled there you can effectively take control of the entire production process. We use the mark camera (down facing) to check 2D bar codes on each board in an array to record exactly which component batches have been placed on each board, and to automatically skip "crossed out" boards without having to set it up manually. We also replaced the library functions to use our existing inventory system.
(If you are interested in using the software I can share further, but it is worth noting it comes with another .NET library that exposes just the hardware interface that you can plug into other software by writing an interface.)
They have 64 CL feeder slots, can support 48 trays and 48 vibratory feeders with the supplied software (but with the code you can adapt that as needed). Realistically you can place 8 trays on the bed at once. It is worth noting that the UI for setting up trays is very simple to use, and supports using external tray feeders if you have need for them. You can pick components from anywhere within the X-Y working envelope and have control over speeds, heights, etc at each step. Re-calibrating the machines is a simple process which you are guided through, although ours was pretty good out of the crate which suggests they QC each before it leaves them*. There are helpful shortcuts for time consuming tasks such as picking the centroids for the outer pneumatic feeders and having it update all the others for you. The English translations are mostly good, with only a few Google Translates needed. I got the impression that quite a lot of development hours went into the software, which is not always the case with cheaper Chinese products.
We looked at a few similar options when choosing the SMT660s and ultimately chose them because for around $10k USD (at the time) you got a lot of hardware for not a lot of dollars.
TBH I'm not sure the 8 head version justifies the extra cost as the rest of the machine is identical.
* Finally worth noting that we had a failure of a front side controller board out of the crate where the input SMEMA interface was damaged and shorted it out. Yingxing sent a replacement out FOC (shipping at cost), so the warranty support was there. This wasn't picked up in QC because they test the machines in isolation.