I have used Tamron, Tokina, Sigma, Vivitar, and Soligor lenses on my Nikon cameras. These lenses served a useful purpose in my lens inventory and were less expensive than their name brand counterparts.
Here are four off-brand lenses that were capable of image quality that was much higher than I expected from an inexpensive lens:
Vivitar 28mm f/2.8 lens with TX mount
Vivitar 35-85mm Series I AI f/2.8 Zoom
Vivitar 70-210mm Series I AI f/3.5 Zoom (made by Kiron)
Tamron 28-200mm f/3.8-f/5.6 Zoom auto focus
With the exception of the 35-85mm, I still own and use these off-brand lenses.
I have also used the following inexpensive name brand lenses that were capable of image quality that was much higher than expected from an inexpensive lens:
Nikon 50mm f/1.8 Series E
Nikkor 75-150mm Series E Zoom f/3.5 AIS manual focus
Nikkor 18-55mm f/3.5 to 5.6 G AF VR
I still own and use all of them.
By the way, I also have an excellent performing Kiron 28-70mm f/3.5 to f/4.5 in a Pentax mount.