How can I tell whether a night vision device offers good value for money?
I would compare the complete package rather than focusing only on the price. I'd look at image quality, range, battery life, construction, controls, warranty, and included accessories. A cheaper device isn't necessarily better value if I end up replacing it after a short time.

I’d compare the whole package rather than focusing only on the price tag. Image clarity, detection range, battery life, build quality, controls, warranty, and included accessories all matter when judging real value. It’s also worth checking established manufacturers such as https://www.agmglobalvision.com/blogs/agm-blog/thermal-ultimate-guide, because their night vision and thermal devices offer different configurations for various budgets and applications. A slightly higher upfront cost can make sense if the device performs reliably, lasts longer, and comes with solid support and useful accessories.