The same 85/1.8 lens is sold under different names, including Neewer, Opteka, Bower, Vivitar, Lightdow, and others. You don't state what camera, mount, or purpose you want these lenses for, so they may or may not meet your needs.

I have used the Neewer 85/1.8 variant.

• It is reasonably sharp, but doesn't feel sharp (acutance) when used wide open. Like most lenses, it improves stopped down.
• It has a definite glow, or halo, which improves when the lens is stopped down to F2.5. (The lens is marked with unusual apertures, like F3 and F6.)
• It's not strong against veiling glare, but the lens hood it comes with is helpful.

There appear to be plenty of people who do like the lens. On a popular shopping site, over 90% of reviews are 4-5/5 stars , and the reviews on YT glow more than the lens does. The lens isn't quite as bad as I remember. It seems to do well outdoors in good lighting. Here's a photo taken at F1.8. Notice the glow and chromatic aberration:

If you search for "85mm 1.8 lens" on your favorite auction site, there are several other options that would likely provide better image quality.

• For a lower price, there are listings for some old Nippon Kogaku manual focus lenses that could be interesting. This was Nikon before they were Nikon. My experience with the brand is they're in line with other lenses from the time. Some people also like "owning a part of history".

• For a little more, there are some Canon and Nikon branded lenses that should perform well. If you're using mount adapters, go with Nikon or Canon FD because it's a pain to control the aperture on Canon EF lenses.

• There's also an 85/1.8 Yongnuo lens, which I have not used. I have used their 50/1.8. It notably had very nice bokeh, but was weak against veiling glare. I wasn't able to assess sharpness, but it seemed sharp enough (acceptable).
• If you can go down to 50mm, there are a lot of old name-brand 50/1.8 and 50/2 lenses with very good image quality. There are many good old third-party lenses as well ("Made in Japan").
• Similarly, there are a lot of good 135/2.8 lenses.