Will there be accurate inexpensive alcotester?

Today there are a lot of resources engaged in the sale of specific equipment on the network. Similar stores offer visitors to purchase an inexpensive alcohol tester. However, a lot of visitors to these online stores doubt the quality of the product. They believe that if the goods are cheap, then it is not of high quality. Quite often this opinion is quite justified. Cheap goods with practical use do not justify itself and becomes a bunch of trash.