I had a few SZHLUX 400w lights that I got with discount codes posted on this thread by
@Marq1340 2 years ago. They put out a lot of light for the price you pay. Pretty decent for a budget light.
I gifted my SZHLUX lights to my neighbor who uses them for vegetable plant starts in late winter through spring. They are still performing well.
The model you posted does not have a pot-style dimmer. It has different modes that switch on/off certain bars to achieve a dimming effect. If I was going to buy an SZHLUX light, I would look at the below model that has a pot-style dimmer.
By pot-style, i mean that it has a dial that appears to be infinitely variable to adjust brightness on all light bars. Not sure if it's actually a potentiometer.
Good luck!
SZHLUX 2023 New 840 Watt LED Grow Light 7×7ft Daisy Chain Dimmable Full Spectrum Grow Light for Indoor Plants, Greenhouse LED Grow Light
https://a.co/d/dzWvJ9L