The other important thing to note when choosing the right online drug screening kit seller is testimonials from previous customers. By checking the testimonials of the previous clients in the field, you will know the quality of the services of the provider in the field. You can also use the testimonials from the previous customers to find out more about the drug screening kits and services of an online drug screening kit store. If previous customers have good or positive testimonials about the supplier, then know it is good and you can go ahead and buy drug screening kits from that shop. However, you should avoid the distributors that clients complain about the services or drug screening kits.