Samyang AF lenses haven’t been around long and initially, they had some AF issues, but Samyang is constantly improving these lenses via a firmware update. If you don’t have a lot of money to spend building out your glass collection or if you’re just getting started in photography it might be best to start with less expensive lenses like Samyang’s before you decide if it’s worth investing in more expensive glass.
Samyang AF 35mm f/1.4 FE: B&H Photo / Amazon / Adorama
https://www.youtube.com/watch?v=zTOO_3OwqGw