I recently bought just this generic cheap one from Amazon, and it's actually been really great (not to discount the other commenter's experience ofc, everyone's body and setup are different but for me it's been super useful). When I'm not wearing it round my neck it's flexible enough to wrap around something and use as a standalone lamp, which is also very nice!

Things I looked for:

• reviews that mention good flexibility but also that the arms stay where you put them
• USB-C charging so you're not faffing with batteries
• adjustable brightness because the light that helps at midday will blind you at night
• adjustable light temperature because warm light is much easier on the eyes at night