A considered starting point
Start with the named model and its current manual. List the light modes, coverage, controller, straps and charging arrangement. A face mask, neck device and panel provide different formats; do not compare them only by the number of LEDs.
Put it into practice
Ask how a damaged strap, controller or cable can be replaced. Follow the manufacturer’s eye-safety guidance and check contraindications. Photographs of glowing LEDs do not measure delivered dose.