I have not tested any of them but I am sure that I will be able to tell you if you are experiencing any side effects from them.
The products that you want to buy need to be good. Some products are very good, some are not, and there are no right or wrong answers. You need to evaluate your own needs, needs of the people you are buying for and the people in your household. For example, you might need to replace a worn mattress, a new pillow, a bedside lamp, or a TV. If you are getting ready to sell some products that you sell on your site, then you can be confident that these products are good for your sleep.
If you are a regular person, you don't want to be getting products that make you feel more tired. If you don't get enough sleep or if you have a bad night's sleep, you could experience sleep problems. If your sleep is problematic, you might need more sleep or even be sleep deprived.
If you have been using the same sleep product for a long time, you may notice a negative effect, or symptoms of sleepiness and insomnia. For example, you may feel sleepy, irritable, and have trouble concentrating.